ALBERT R. MANN LIBRARY New York State Colleges of Agriculture and Home Economics Cornell University Cornell University Library SB 211.P8T16 Potato growing in New Zealand 3 1924 003 299 793 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924003299793 NEW ZEALAND PRACTICAL HANDBOOKS Potato Growing in New Zealand BY DAVID TANNOCK, F.R.H.S. Superintendent of Gardens and Reserves, Dunedin r WHITCOMBE & TOMBS LIMITED Auckland, Christchurch, Dunedin, and Wellington, N.Z. Melbourne and London . Agriculture A TEXT BOOK for New Zealand Schools ana Colleges, covering the entire lield of Agriculture for all examination candidates. SECOND EDITION Revised Agriculture Pri 6 6 By R. P. CONNELL, MA., J. W. HADF1ELD and Others. The best hook published on the subject WH1TC0MBE & TOMBS LTD. CONTENTS Introduction The History of the Potato IJotany of the Potato Soils Manures Propagation Garden Cultivation Farm Cultivation New Potatoes from Old Ones Varieties Tools, Implements and Machines Diseases of the Potato Fungoid Pests Insect Pests Ways of Using Potatoes PAGE 7 id 1 6 21 25 35 55 6? 77 79 86 90 90 99 105 LIST OF ILLUSTRATIONS FACING PAGE Potatoes Placed in Boxes to Sprout . . 22 Boxes Stacked in Open Air . . .22 " Strong Seed '' . . 39 Good and Poor Seed . . . . 39 Over-sprouted Seed . . 46 How Shoots Arise . . 46 Planting with Dibber . . 55 Planting in Shallow Drills . . 55 Breaking up Rough Ground . . . . 70 Potato Planter . . . . . . 70 Potato Digger . . . . 78 Rows Thrown Together After Digging . 7S Irish Blight . . . . 86 Potato Moth . . . . 8(1 Potato Attacked by Irish Blight . . 103 Earthed Up Ready for Spraying . . . . 103 POTATO GROWING INTRODUCTION. The cultivation of the potato received a great impetus during the five years of war, for when the food situation became serious it was at once recog- nised that a greater quantity of food could be pro- duced from the humble tuber than from any other plant. Other advantages it possesses are that no expensive machinery is required for either its culti- vation, harvesting, or preparation for food, and that a small plot can be cultivated almost as economically as a large area. A person with a few square yards of garden can produce quite a reasonable proportion of the food required for himself and family by planting potatoes, whereas if a similar area were planted in any grain crop the amount of food produced would be quite insignificant. The cultivation of the potato, up to a certain degree, is also better understood by the average person than that of any other crop; consequently, all that was required was to provide the workers with a piece of land and some good seed and they could produce a crop with reasonable certainty. This cultivation whether carried on in a garden or allot- ment while the person followed his or her usual work, provided a pleasant and profitable change of occu- pation for anyone employed in an office, shop, or factory. In this Dominion, though the cultivation of the potato has reached very considerable dimensions, the average crop has so far not exceeded the amount A 8 POTATO GROWING required annually for food purposes. Some years there is a surplus available for export, but on an average there is a shortage, and prices are high. There is not the slightest doubt that the growing of potatoes for manufacturing purposes could be carried out very profitably in the districts which seem specially suited for their cultivation. The production of starch from imported rice seems to be a waste when it could be produced equally well from Dominion grown potatoes; and the manufacture of potato spirit suitable for various manufacturing and other purposes could also be profitably carried out, for all tubers, whether diseased or not, can be utilised. It would not, however, be possible to establish indus- tries on the chance of a surplus over ordinary require- ments. A definite quantity of tubers would have to be guaranteed every year, in addition to the refuse and those unsuitable for food purposes. This book has been prepared with the idea of helping those who may be taking up the cultivation of the esculent tuber for the first time, also those who may be taking up its cultivation on commercial lines. The writer has had practieal experience in the culti- vation of potatoes in Scotland, in the tropics, and in this Dominion, and this work is the result of experi- ence gained under various climatic and soil conditions. There is no doubt that farmers and others pay far too little attention to all the little details of culti- vation which make all the difference between success and failure, and that too much is left to Providence and the climate. This is probably the reason why the potato crop is such an uncertain one. One year there is far more than can be consumed for food, and prices are low; another year the crop is almost an entire failure, and prices are high, if not actually prohibitive. INTRODUCTION 9 This crop ought to be a more regular one, and the adoption of more reasonable methods of soil prepar- ation and manuring, sensible and thorough methods of cultivation, and, above all, scientific methods of seed selection and spraying, would enable growers to rise superior to climatic and other conditions, and would free them to a large extent from the terrors of blights and epidemics. Considerable emphasis has been placed on the importance of proper seed selec- tion, for neglect of this is undoubtedly the weak link in the chain of potato cultivation. It does not pay to plant cheap seed or to stint the amount planted per acre. Probably it would be better for farmers or seed growers who have special soil and climatic conditions to make a speciality of growing potatoes for seed, and it would certainly pay those who have neither the necessary knowledge nor time to devote to selection to purchase pedigree seed from a reliable source. "With regard to the terminology employed in the text the word "shaws" has been used for "leaves" and "stems" for "haulms." The word "seeds" has often been used to mean "sets," for though sets are quite unlike true seeds, the use of the term "potato seed" is common in books and catalogues. No calendar of operations has been provided, as the time of planting and the time of digging must vary throughout the Dominion according to the locality and the soil. In some districts, owing to special conditions, it may be found necessary to depart from the details of the instructions given, but on the whole they will be found suitable for most of the potato growing lands in the Dominion. The illustrations have been prepared from photo- graphs taken in the Dunedin Botanic Gardens, where 10 POTATO GROWING the growing of potatoes for seed purposes has been carried out most successfully and profitably for several years past, and also from Agriculture, by R. P. Connell and J. W. Hadfield. Some of the manurial and other experiments described were carried out by the late Mr. Healy while Agricultural Instructor for the Otago Educa- tion Board, and are very convincing. THE HISTORY OF THE POTATO. The introduction of the potato for cultivation in Europe is, comparatively speaking, so recent that one would expect correct information would be available as to when and how it came about, but this is not so, and there is a good deal of uncertainty and mystery about it. This is probably due to the fact that the potato was not at first looked upon as an im- portant article of food, and it was not until long after its introduction that its true value was recognised. It is a native of the dry mountainous regions of Chili and Peru, where it is found growing in a semi- wild state, and the Spanish explorers and conquerors of this territory found the tubers an important article of food and commerce among the native tribes. They are said to have transplanted it from South America to Virginia, whence it was taken to Europe. It is stated that it was introduced to Ireland by the settlers who were sent out to Virginia by Sir "Walter Raleigh in 1584. When they returned in 1586 they brought back the potato with them, and it was first planted on Sir Walter Raleigh's estate at Youghal, near Cork. It is remarkable that to this day the potato is more extensively cultivated and more generally esteemed in Ireland than in any other country. HISTORY OF THE POTATO 11 It is also stated that it was sent from Virginia to Spain and thence to Italy where it received consider- able attention from an Italian named Cardone, and that the Italians were the first to take kindly to this new tuber as a food crop and to give special attention to its cultivation. Prom Italy its cultivation spread to the other countries of Europe. Its progress, however, was not rapid, and it was not until centuries later that its true value as a food crop was recognised. It is more than likely that the first introductions were comparatively poor tubers, being waxy and deficient in flavour. One can easily understand the people of those days looking with distrust upon a plant which produced its crop under the ground and was, moreover, closely associated botanically with the Deadly Nightshade and other useless weeds. A famous French botanist, Oliver de Serres, deemed the tuber worthy of a special chapter in a book which he published in 1600, and to another Frenchman, M. Fruzier, it owes its popular name, "pomme de terre," the apple of the earth. To a third Frenchman, M. Parmentier, the potato owes much of its popularisation as an article of human food. It is stated that he induced Louis XVI. to order a large tract of land to be planted with the tubers, and that to popularise it further the King wore a flower of the potato in his buttonhole. It is certain that Ireland was among the first countries to take up the cultivation of the tuber on a large scale. The climate and the soil seemed to suit it, and until quite recently the area of land in potatoes in Ireland was about equal to the area under this crop in the whole of Great Britain. Not until 1663 do we read of the cultivation of the potato on a large scale taking place in England, but 12 POTATO GROWING in that year it received a great impetus owing to the efforts of the Royal Society, prompted, it is said, by a recognition of the food value of the tubers in a time of scarcity, to encourage its production. The cultivation of the potato made little progress in Scotland until about the middle of the eighteenth century, when famine and widespread destitution forced its claims on the Scottish farmers. Once the initial prejudices were overcome the culti- vation of the potato made steady progress in all temperate countries, and it received no cheek until 1842 when the blight known as the potato disease attacked the plant. This disease first made its appear- ance in Germany, and spread rapidly through Europe, reaching even Canada and the United States, and everywhere it threatened to exterminate the potato growing industry. The effect of the blight was so disastrous in Ireland that a famine followed, and to this day it is called the Irish blight when it ought more justly to be called the German blight. At first growers were in despair, and many con- sidered the cultivation of the potato doomed, but no sooner did the trouble appear than farmers, gardeners, and scientific men set about trying to discover a remedy. They attacked the problem from three directions. The first method adopted was to raise new varieties which would be more vigorous than the kinds then in cultivation, and in this direction very considerable success was obtained. For this the chief honours belong to William Patterson, of Dundee, who was probably the first individual in the United Kingdom to cross-fertilise the potato. His experiments were started long before the disease appeared, but it was not until he had worked at them for 30 years that he succeeded in raising Patterson's Victoria, a variety HISTORY OF THE POTATO 13 which can claim as its descendants most of the best varieties in cultivation at the present time. Patterson placed some score of other varieties on the market, and he is claimed by some to be the saviour of the potato. Other famous raisers of new varieties of potatoes were Clark, who raised Magnum Bonum, for a number of years the best disease resist- ing variety; A. Pindlay, who raised the famous variety Up-to-Date, probably still one of the best in cultivation; and Carter, Chapman, Daniels. Sutton, Fenn, Fidler, Forbes, Harris, Kerr, Sharp, "Webb, and Dobbie. The second method adopted to check the disease, which is caused by a fungus Phytophthora infestans, was to apply some kind of fungicide, and the success of the Bordeaux mixture in checking the disease on vines suggested its use on the potato. By spraying once, twice, or even three times, the disease is un- doubtedly kept in check if not completely extermin- ated. The third method suggested by some growers was a more reasonable selection and treatment of the sets to preserve the full vigour of the shoot which is to become the new plant. This may be described in brief as the selection of immature sets, greening and storing in the open air as far as possible to retard growth, and sprouting in boxes before planting. By a combination of all three methods we are now able to keep the potato disease in check, and to grow good clean crops ; but it is doubtful if farmers, even now, fully realise their responsibility, as so many of them still adhere to their old-fashioned, out-of-date methods, trusting, apparently, to Providence to inter- vene in their behalf. In New Zealand we have a climate and soil capable of producing the very best crops of potatoes. Hence 14 POTATO GROWING it seems strange that we seldom produce sufficient for home consumption but actually import from Aus- tralia, although the prospect of high prices should tend to increase the area put under this crop. It is remarkable that, centuries after the Royal Society first boomed the potato, it should be called upon to save Britain from starvation, when, owing to the submarine piracy of Germany, so many food ships were destroyed. The cultivation of the humble tuber was taken up by all and sundry, gardens and parks were ploughed up and planted with potatoes, and workers took up allotments wherever they were available, their chief crop being the potato. Better methods of cultivation, involving greening and sprouting, spraying, etc., which were previously carried out by a few, became the general practice, and through the action of the Press and many Horti- cultural and Agricultural Societies potato growing became better understood than ever it had been before. No history of the potato would be complete without a few lines on the great potato boom when some varieties were sold at such a high, price that they were worth their weight in gold. The boom started in 1902 when the circumstances were favourable, and it continued to the end of the 1904 season. During that period the weather conditions were very bad, disease was very prevalent, supplies were short, and prices very high. While the boom was at its height two new varieties were introduced which were reported to be disease resisting and immense croppers. During the winter of 1902-1903 prices for either of these varieties were forced up to an unprecedented level. At the end of the following season, when the disease was again very prevalent and prices for sound tubers very high, a perfect frenzy seemed to seize HISTOKY OP THE POTATO 15 upon growers. Day by day and week by week news- paper readers were treated to all sorts of sensational statements as to the prices paid for tubers of particu- lar varieties, and as these reports increased, buyers went quite mad. It was reported that prominent growers were paying from £25 to £100 for a single tuber, and it was stated with authority that three pounds of these precious tubers were sold at £160 per pound. The public appetite for these new varieties seemed to be insatiable and scores of new varieties appeared, many of which were old friends with new names, and these were rushed upon the market and eagerly snapped up at fancy prices by credulous growers. Even at the termination of the planting season of 1904 the delirium had not subsided. The boomers erected greenhouses and started to force these precious tubers which were sold at £160 per pound. People who could not afford to buy a whole tuber were encouraged to buy one or two rooted cuttings at from £2 to £4 each. It is stated that one developer boasted that he had taken 100 shoots off a single tuber, so that if he sold all these at an average of £3 each he would make a handsome profit and still have his precious tuber left. The potato crop of 1904 found the growers of the high-priced varieties in a very different frame of mind. Their precious shoots which they had pur- chased at from £2 to £4 each yielded a caricature of a crop, as any one with a knowledge of botanical science and farm and garden practice could have told them would be the case. The intense propa- gation, while yielding plants, ruined their constitu- tion, and they not only failed to crop but were quite as susceptible to disease as the older and cheaper varieties. 16 POTATO GROWING The fact that the crop in 1904 was a very good one and prices ruled low also helped to burst the boom. People who had paid high prices for a few tubers with the idea of propagating them and selling high- priced seed lost heavily; for growers had learned a lesson and looked with suspicion on much-advertised and high-priced kinds. Even now when well-tried, new varieties are being introduced at reasonable prices, growers are wise to test them before discarding their older and reliable kinds, for by proper seed saving and sprouting it is considered that there need be no deterioration. BOTANY OP THE POTATO. The potato belongs to the natural order Solanaceas or Nightshade Family, an order widely distributed in tropical and subtropical countries, but chiefly found in tropical America. This order includes other well-known economic plantssuch as Lycopersicum esculentum (the tomato), Solanum melongena (the egg plant), Nicotiana iabacum (tobacco), Solatium eapskastrum (Cayenne pepper), Capsicum baccatum (chillies), such medicinal plants as Atropa belladona (deadly night- shade), Hyoscyamus niger (henbane), Solarium dul- camara (bitter sweet), and Solanum nigrum, and such ornamental plants as Solanum jasminoidcs (a favourite climbing plant), S. crispum, S. Seaforthi- anum, and X. Wenalandi, all ornamental climbing plants. The native bulli-bull or poro-poro, Solanum ai'irulare. and the Schizanthus Wisctonensis. a favourite greenhouse plant, also belong to this order. The genus solanum contains about 700 species, and of these the following are tuber bearing: — Solanum BOTANY OP THE POTATO 17 tuberosum, S. Cammersoni, S. cordiophyllum, and 8. Jamesii. Solanum is an old Latin name used by Pliny, and means soothing or quieting, and no doubt refers to the medicinal properties of some • members of the genus. Solanum tuberosum, the potato, is a herbaceous perennial, usually with much branched, tender, herb- aceous tops commonly called shaws; and the flowers which are usually white or lilac are borne on long stemmed dichotomous clusters. The corolla is prom- inently lobed, stamens five, inserted on the throat of the corolla, the anthers opening by means of special pores or slits, ovary usually loculated, and the fruit ripening into a berry containing from 200 to 300 seeds. The potato has two methods of reproducing itself, the one sexual from true seeds, and the other asexual by means of tubers. As the production of tubers has been so strongly developed in many of the newer varieties they seldom produce good seeds though they often flower freely. The tuber is an underground stem specially modi- fied for the purpose of storing up plant food, chiefly in the form of starch. This food is again used up in the development of the new shoots when growth commences in the spring. The roots absorb water with mineral matter dis- solved in it, which is passed up the central part of the stem to the green leaves, where, in the presence of sunlight and the carbon dioxide inhaled by the leaves, starch is formed. This process is called assimilation, and the first product which we can detect as a result of assimilation is starch. As, how- ever, starch is insoluble in water it has to be changed into another product, sugar, before it can pass down 18 POTATO GROWING through the tissue of the exterior layer of the stem and the interior layer of the bark to the tuber, where it is again converted into starch and stored up. The outer skin of the potato consists of a thin, greyish brown, corky substance, which corresponds roughly to the bark of an ordinary stem, and a cross section of the tuber shows in addition to the skin a cortical layer which is slightly coloured, the tint varying with the variety of the potato, but like any other stem it turns green when exposed to the sun- light. This layer is denser than the other parts of the tuber, and it contains many fibre- vascular bundles, especially on the inner edge where a marked ring of them plainly separates this layer from the rest of the tuber. The interior or flesh of the tuber is made up of two layers, the outer medullary layer and the inner medullary area. The outer layer forms the main bulk of a well developed potato, and contains the greater part of the food ingredients. The inner medullary area, sometimes called the core, appears to spread in irregular arms into the outer layer; it contains slightly more cellulose and less water and nutrients than the outer medullary portion. When rubers grow to a great size the inner tissue is often ruptured, and they become hollow. As in all other plant forms, the framework of the tuber is made up of cellulose, a carbohydrate or group of carbohydrates familiar in many forms such as cotton, flax, and the bran of wheat. The cellulose forms the walls of the network of cells which in turn comprise the body of the tuber and in which are contained the cell sap and the starch grains. When the containing cells are ruptured or broken, as is the case when potatoes are grated into water, the starch, whicli is insoluble, falls to the bottom of the vessel BOTANY OP THE POTATO 19 and the water can be poured off leaving the starch grains behind. In this way ordinary potato starch is obtained, and by washing it several times a potato flour is prepared similar in appearance and properties to arrowroot. Cultivated varieties of potatoes vary not only in the appearance of their leaves, flowers, tubers, habit of growth, and the time they take to mature their crop of tubers, but also in the proportions of carbo- hydrates, water, fats, protein, and mineral sub- stances they contain. They vary also according to the soil and climate in which they are grown, so that a variety which is dry and floury and of good flavour when grown in one district may be wet and waxy and devoid of flavour in another. Though the cultivated varieties of potatoes vary the average analysis is as follows : — Water .. 78-3% Ash .. .. 1-0% Starch . . 18 -0% Crude fibre . . -4% Protein . . 2 -2% Fat . . . . -1% The corky skin of the potato makes up about 2-05% of the whole tuber and the cortical layer 8-5%, leaving 89% for the medullary area. Theo- retically the skin is the only refuse or inedible part, and when the tubers are cooked in their skins it is the only part removed, but when they are pared or peeled a considerable portion if not all of the cortical layer is removed. The edible portion, excluding both the skin and the cortical layer, consists of about 78% water and about 22% of food constituents. The carbohydrates are by far the most abundant of the nutrients, and of the 18-4% less than 0-5% is made up of cellulose, so that potatoes cannot be said to be indigestible on account of the cellulose which they contain. The bulk of the carbohydrates which the potato stores up for future use is in the form of 20 POTATO GROWING mature. In old potato tw I tabers become The most important mineral matters found in the tabers are potash and phosphoric acid compolfc in all nnTt rCaSOn ^ *"" minerals are &WW in all potato manures. If pH-d potatoes are exposed to the light and air the outer surface turns brown. This is due to the action of enzymes or unorganised ferments naturally present in the tubers. In the presence of oxygen of the air they act upon the tannin-like bodies in the tubers m Mich a way as to change their colour. This browning is prevented by putting the peeled tubers in salted water, or even pure water, which keeps the air from getting at them. From the foregoing remarks it will be seen that botanieally the potato is a very complex organism, and that though the production of tubers depends on the development of the foliage it often happens that plants which produce a rank growth of shaws produce a poor crop of tubers, and these are often ngly and deformed. The growth and feeding of the plant ha> to be so evenly balanced that the production of starch and its storage in the tubers is carried out to the maximum efficiency of the plant, and that it is not used up in the excessive production of roots and foliage. This often happens in a moist soil containing an excess of nitrates. The potato plant has three stages of development. (1) When it is drawing its supplies of food from the old tutors (2) when it is developing its true roots, which absorb water and mineral plant food, and SOILS 21 throwing up stems and leaves; (3) when the develop- ment of the tubers and the storage of starch is carried out. The first is called the sprouting, the second the growing, and the third the ripening period. SOILS. Though potatoes can be grown successfully in soils differing widely in their composition, two things are essential in all good potato districts. These are good drainage and a liberal supply of organic matter or humus. Probably the least suitable soils are heavy wet clays. These readily become waterlogged and puddly when wet, and when dry they shrink, crack, and become too hard to be penetrated by the soft roots of the potatoes or the tender underground stems on which the tubers are produced. Heavy clay soils are usually late soils, and there is the double danger of the young plants being frosted in spring and of the old plants being brought to a sudden and premature end in the autumn through early frosts. Potato land must be thoroughly well cultivated and loose in texture, and this is almost impossible on heavy clay land. Though it would be unwise to go in for potato growing on a commercial scale on heavy land the farmer has often no choice, but has to make the best of the soil available in order to grow sufficient potatoes for his own requirements. In almost any soil, provided sufficient labour and correct treatment are given, fairly satisfactory crops can be grown, though the quality of the product may leave much to be desired. When preparing a heavy soil it must be thoroughly cultivated to a considerable depth, trenched at least two feet deep, well drained, and thrown up rough to 22 POTATO GROWING expose the maximum surface to the disintegrating influences of frost and air. A considerable amount of organic matter such as fresh strawy manure, peat, compost heap, weeds, straw, or wet hay should be worked in, as decaying vegetation not only acts on the insoluble matter in the soil converting it into plant food, but has the mechanical effect of opening the soil and greatly improving its texture. Such inorganic materials as sand, wood ashes, lime rubble, gravel, and reasonable dressings of unslacked lime will also be an advantage. A clay soil is one composed of from 75% to 100% of clay, and a clay loam which contains from 50% to 75% is much easier to cultivate and bring into a condition suitable for potato growing, though it would never be considered a good potato soiL By treating it in the way recommended for a clay soil, cultivating it deeply, draining it well, adding plenty of strawy manure and other organic matter, and applying light dressings of unslacked lime, it would grow good crops of later varieties, though it would probably be too cold for early sorts. A loam which consists of 50% clay and 50% sand is a good soil when well cultivated, provided there is a reasonable amount of humus in it. Newly broken up grass land or land which has been newly cleared of bush or scrub will produce very heavy crops of potatoes so long as the supply of organic matter is maintained, either by manuring or ploughing in catch crops or green dressings. A sandy loam which consists of from 25% to 50% of clay is an ideal potato soil : it is easy to drain, easy to cultivate, and does not become cold and waterlogged during wet weather, or lumpy when dry ; there is not the same danger of late frosts, and owing to the good drainage the liability to disease is not so great. Seed Potatoes placed in box to sprout. See page 41. Potatoes in boxes stacked behind a wall in the open air. See pages 42-45. soils 23 Potatoes can be grown quite successfully in gravelly soils, light sandy loams, or even in almost pure sand, provided there is a reasonable amount of humus present, and it is the constant endeavour of the farmer to prevent the humus from deteriorating or disappearing altogether. In the Bermudas, where crops of early potatoes are grown for the New York market year after year in the same soil, the proportion of humus is maintained by adding large quantities of seaweed which is cast up on the beach by the northern flow of the Gulf Stream. In some cases this is collected and used for bedding pigs or is stacked up until partly decayed before it is ploughed or dug in. In Ayrshire, where potatoes are grown very exten- sively on the sandy soils along the coast, seaweed is used extensively by some growers to replace the or- ganic matter, and on some farms it is applied at the rate of 40 tons to the acre. Very good crops of potatoes have been grown on the sand hills near Dunedin. Crops of lupins had been growing on the sand for several years previously, and there was a layer of humus several inches thick formed by the dropping of the leaves, twigs, and seed pods; and the roots with their nitrogen gathering nodules which were left when the clearing was done also added to the fertility of the sand. The lupins were cleared and burned in heaps, the ashes being spread on the surface and lightly dug in. The crop was good and the tubers clean, dry, and free from blemishes, but it would vary according to the season. During a very dry year the development of the shaws would be incomplete and the crop of tubers propor- tionately small. On a sandy beach the supply of humus could be maintained by applying seaweed, strawy manure, or the humus collected from under the surrounding lupins. 24 POTATO GROWING Early planting of quick maturing varieties should be practised on sand, for after the beginning of the New Tear it is usually too hot and dry, and this would induce premature ripening with a diminished crop. The nature of the subsoil also determines to a large extent the suitability of a locality for the growth of potatoes, and in Scotland the best potato districts are those which overlie the old red sandstone. This pro- vides complete natural drainage, though in most cases tile drains are also provided. In New Zealand the best potatoes are grown on soils which overlie sandstone, limestone, gravel, or pumice, all of which provide excellent drainage, and the soils also, to a very considerable extent, repeat the character of the subsoil. They are easy to work, and not only do they produce good crops except in very dry years but the quality of the tubers is also excellent. Oamaru has long been famous for its potatoes though in some cases the humus in the soil has been allowed to deteriorate, and there is not sufficient attention paid to obtaining seed from a late district, and to spraying for the blight. River valleys and the flat land near the mouths of rivers are most suitable for potato growing, particu- larly when formed by the disintegrating of mica schist rocks, such as occurs in the valley of the Molyneaux in Central Otago and in the delta at its mouth. These alluvial lands are usually of great depth. They are moist, while at the same time they are well drained; for they have usually a shingly bottom and are rich in humus and alkaline substances. Some of the heaviest crops of potatoes in the Dominion are grown on Inch Clutha. The tubers come out clean and they sparkle with the particles of mica that adhere to their skins. Peaty soils, which are almost pure humus, also grow MANURES 25 excellent crops of potatoes, provided ample drainage is given to keep the water level two feet or more below the surface. Where drainage is difficult owing to the lack of sufficient fall to an outlet Chinamen draw the soil up in ridges, from a foot to eighteen inches high, and on the tops of these the potatoes are planted, moisture loving crops being grown in the hollows between the ridges. This provides a certain amount of drainage but in very wet springs the sets often rot in the ground and growth is very much retarded if not completely stopped for a time. Peaty soils are usually sour owing to the superabundance of organic acids, and these acting on the tender skins of the tubers cause wart-like growths which do not look attractive, though they do not in any way spoil the crop. Potatoes grown in well drained peat usually come out clean and smooth. Heavy crops are obtained, as this soil seldom suffers from drought. MANURES. When we take up the cultivation of any crop the question of manures and plant foods becomes one of the first considerations, and the correct application of manures plays a very important part in successful potato growing. This question has to be approached from two directions: first, we need to know what the potato requires; and secondly, how many of the materials which the crop requires to enable it to develop to its full extent are already in the soil in sufficient quantities. It is usually understood that newly broken up virgin soils contain all the plant food that will be required to produce full crops for a year or two at least, but as it is the minimum quantity of any of 26 POTATO GROWING the food constituents which determines the crop, it might fail even though all food constituents but one were present in abundance. For example, potato plants require nitrogen, potash, and phosphoric acid, and if the supply of potash, for instance, be short, even though there be sufficient nitrogen and phos- phoric acid present for several crops, the plants will be starved, and a poor crop will be the result. Potatoes require an all round diet consisting of nitrates, phosphates, and potash, and it is found by experiment that potash takes a very important place in any potato soil. In fact, in many soils it is the determining factor, and must be added in some form or other to secure healthy growth. The manures usually applied in both field and garden cultivation are farmyard manure, seaweed, compost heap, leafmould, superphosphate, basic phos- phate, guano, basic slag, kainit, bone meal, phos- phatic guano, muriate and sulphate of potash, sul- phate of ammonia, nitrate of soda, sulphate of iron, sulphate of lime, lime, magnesium salts, soot, and wood ashes. Of the above, farmyard manure, compost heap, seaweed, and leafmould are considered general manures because they supply all the necessary con- stituents of a complete plant food; but, unfortun- ately, they vary so greatly in the quantities of the essential constituents which they contain that they have usually to be supplemented by a certain pro- portion of some special manure or combination of special manures. Farmyard Manure. — This is considered to be in- dispensable in all except a very few cases, and on some farms where a definite system of rotation of crops is followed, all the manure available is put into MANURES 27 the potato or turnip crop. Farmyard manure varies according to the nature of the animals, the kind of feeding they get, and the method in which it is collected and stored. Chemically it contains small quantities of phosphoric acid, potash, and nitrogen, all of which are essential, but, as a rule, there is not sufficient potash to provide for a heavy crop and the quantity of available phosphoric acid is also limited. From a mechanical point of view farmyard manure and the other general manures mentioned play a very important part. They bind together light and sandy soils enabling them to retain moisture and soluble plant food, and by darkening the colour of soils they increase their power of absorbing and retaining sun heat. These general manures also assist in breaking up heavy, stiff clay soils, increasing their porosity and enabling the roots and the tender underground stems of the potatoes to penetrate them in all directions. Though these natural or general manures are essential, they are, in many cases, not sufficient in themselves, and if applied in too large quantities have a tendency to encourage an over luxuriant growth of stem and leaves which does not ripen properly and is very susceptible to an attack of blight. When the growth is too luxuriant, even though the tubers develop, they are large, coarse, wet, and badly matured. It will be evident, then, that farmyard manure has to be applied with caution, and that in many cases green manure, leafmould, and compost heap which contain less available nitrates are more suitable. 28 POTATO GROWING To show the effects of humus in the soil on the yield of potatoes, experiments were carried out at the District High School, Tapanui, by the Agricultural Instructor for the Otago Education Board. Plot A received no humus of any kind. Plot B was planted with the annual white lupins the previous year, and these were dug in in early winter. Plot C had an old haystack bottom dug in in the winter. Plot D had a three year old compost heap dug in during the winter. Each plot received a dressing of 4 cwt. of basic phosphate at the time of planting, and the same variety of seed, viz., Up-to-date, was planted. The distance between the rows and between the sets in the rows was the same, and the subsequent culti- vation was the same for all the plots. The results were : — Plot A yielded 6 tons per acre. B 9 r ii » D „ 18 „ „ The inference is that humus greatly increases the yield and that the better decayed it is at the time of application the more valuable it is as a fertiliser. Seaweed. — This is an excellent manure for potatoes wherever it can be obtained easily and cheaply. It contains from 4 to 20% of potash and about 3% of nitrogen, and when it has been used as litter for pigs it forms a very valuable addition to light sandy soils. It is either dug in or ploughed in in the autumn at the rate of from 40 to 50 tons per acre. MANURES 29 Phosphatic Manures. — Experiments have proved that phosphates are absolutely necessary in some form or another for the successful cultivation of the potato, and all special potato manures contain a con- siderable quantity of them. The various phosphatic manures are superphosphate, basic phosphate, dis- solved bones, bone meal, basic slag, and phosphatic guano. Now that we are to have 16% of the annual output of phosphate from Nauru Island, an abundant supply of this invaluable manure should be assured. The acid forms, such as superphosphate and dis- solved bones, act more quickly than the basic forms and are more suitable for soils which contain con- siderable quantities of lime, are well drained, and are fairly light. The basic forms, such as basic slag, basic phosphate, guano, and bone meal, are slower in action and are suitable for sour and undrained lands, those which are deficient in lime and are rich in organic matter or peat. Potash Manures. — In is universally agreed that potash in some form must be present in considerable quantities in all potato soils or it must be applied in the form of manure to get the best results. Many soils, such as clays for instance, already contain con- siderable quantities of potash, and though the appli- cation of this manure may not do any harm to the crop it would not materially increase the yield and would be an unnecessary expense. A few simple manurial experiments would soon demonstrate whether the crop required additional potash or not. Light soils, sandy loams, chalks, peats, and sands, usually styled good potato soils, all require potash manure in some form. In normal times, potash can be obtained in three forms, i.e., kainit, muriate, and sulphate; but as the 30 POTATO GEOWING bulk of the potash used to come from Germany the supply has been almost cut off since August, 1914. Other sources of supply have been discovered, and supplies will soon be normal again. Kainit is a crude form of potash manure. It is the cheapest, and as it also contains a small pro- portion of magnesium salts it supplies what is necessary of the latter as well. It is somewhat slow in action and has to be applied during the winter or early spring when soil preparation is being carried out. Muriate or chloride of potash is often recom- mended. It is richer in available potash than kainit, one ton of the former being equal to four tons of the latter, and is correspondingly dearer. In action it is like kainit, but it is reported to have a tendency to cause waxiness in the tubers if present in excess of actual requirements. Sulphate of potash is perfectly harmless, the potash becomes available readily, and unlike kainit it can be applied at the time of planting. Sulphate of iron is strongly recommended by some authorities. It is an important ingredient of potato manures, and is said not only to assist in increasing the yield of tubers, but also to act as a preventive of the dreaded blight. According to Dr. A. B. Griffiths, an application of iron sulphate will give a greater yield than one of kainit, and he asserts that in the experiments made with kainit and iron sulphate, the crop dressed with the former was diseased while that grown in the plot dressed with the latter was free from disease. This is a problem awaiting further investigation under local conditions as to climate and soil. MANURES 31 Wood ashes are also an important source of potash, and for small plots in garden cultivation it should be possible to obtain all that is necessary from the rubbish fire and from fires in which wood is burned. As the potash is readily washed out it is desirable to collect the ashes before they become soaked with heavy rains and to store them under cover until they are required. The best time to apply them is to spread them on the surface so that they may be worked in during soil preparation. Not only do wood ashes supply the crop with potash but the small particles of charcoal, partly consumed rubbish, and biirned soil greatly assist in improving the mechanical condition of the soil, especially heavy clays. Nitrogenous Manures. — Apart from farmyard manure, nitrate of soda and sulphate of ammonia are the chief nitrogenous manures, and when good farmyard manure is used there is little need for either of the latter two. Good farmyard manure, however, is usually very scarce, and when such other general manures as compost heap, leafmould, green manure, or seaweed are used, a light dressing of either sul- phate of ammonia or nitrate of soda is necessary. The tendency of nitrogenous manures is to promote a luxuriant growth of stem and leaf, to keep the crop from maturing early, and to predispose the plants to attacks of disease. Both sulphate of ammonia and nitrate of soda become available very readily and should be applied when the plants are through the ground so that the roots may absorb them at once. Soot, malt dust, or dried blood are excellent nitro- genous manures for early crops, and can be applied at the time of planting. There are both phosphatic 32 POTATO GROWING and nitrogenous guanos. The former are applied at the time of planting and the latter as a topdressing later. Fowl manure if mixed with lime or gypsum and stored in a dry place is useful, but it is strong and has to be applied with caution. Lime is an important ingredient in all potato soils, not only because of the excellent mechanical influence it exerts but because of the chemical action it has on other ingredients in the soil, some of which are harm- ful to plant growth. Mechanically it exerts a power- ful influence on heavy clay soils, causing the very fine particles to coagulate into larger ones rendering them less plastic and sticky and easier to drain and cultivate, but it also binds together loose sands rendering them less susceptible to loss of moisture and soluble plant food. Lime also exerts a powerful influence on sour soils such as peat, those rich in organic matter, and old garden soils which have been cultivated and manured for generations. It neutralises the acidity and, to use the common term, sweetens them. Lime also assists in rendering the insoluble plant food in the soil soluble and available. It acts upon vegetable acids, liberates ammonia, and encourages the formation of nitrates in the soil by acting as a base to take up the excess of soluble nitrates and hold them until the roots of the plants are ready to make use of them. Lime, when applied in the caustic or quicklime form, has also an important effect in destroying the various insect and fungoid pests which infest the soil. As lime quickly washes down into the subsoil it should be applied on the surface at the time of soil MANURES 33 preparation in late winter or early spring, and the most suitable form for soils rich in organic matter is what is known as crushed agricultural lime. Over- liming is a great mistake, and because it is cheap compared with other manures farmers are apt to use overmuch of it. It is much better practice to give a light dressing every year than a heavy one once in a while, and about half a ton per acre is quite sufficient for potato crops. The following experiments were carried out by the Irish Department of Agriculture over a period of three years, and though the values of the crops and the cost of the manures were stated these details have been omitted as they have little local application. To obtain the heaviest crop in the shortest possible time is the main objective, and a good crop always pays even when potatoes are comparatively cheap. No. of Plot Manure applied per acre Average total yield per acre Increase due to manures 1 No manure Tons 3 Cwts. 1 Tons Cwts. 2 20 tons farmyard manure ... 8 2 5 1 3 1 K 7 2 i 8 i 15 tons farmyard manure, 1 cwt. sulphate of ammonia 8 6 5 5 5 15 tons farmyard manure, 1 cwt. sulphate of ammonia, i owts. superphosphate ... 9 10 6 9 6 15 tons farmyard manure, 1 cwt. sulphate of ammonia, 4 cwts. superphosphate, 1 owt. muriate of potash . . . 10 5 7 i From the above it will be seen that the general manure produced the largest crop, and that a fair dressing of farmyard manure with each of the necessary chemical manures was the most satisfactory. 34 POTATO GROWING Further experiments to discover the chemical manures most suitable for supplementing the 15 tons per acre of farmyard manure : — No. ot Plot Manure applied per acre Average total yield per acre IncreaBe due to chemicals 1 15 tons farmyard manure . . . Tons Cwts. 7 9 Tons Cwts. 2 15 tons farmyard manure, 1 cwt. sulphate of ammonia 8 6 7 3 15 tons farmyard manure, 1 cwt. sulphate of ammonia, i cwts. superphosphate ... 9 10 2 1 4 15 tons farmyard manure, 1 cwt. sulphate of ammonia, 4 cwts. superphosphate, 1 cwt. muriate of potash ... 10 5 2 10 From the foregoing it will be seen that the best results were obtained from a complete mixture of chemical manures such as would be provided by most of the standard potato manures on the market. The results of experiments carried out by the Glasgow and West of Scotland Agricultural College were very similar to those obtained in Ireland. The best results were obtained from a dressing of 10 tons farmyard manure, 4 cwt. superphosphate, 1 cwt. sulphate of ammonia, and 1^ cwt. sulphate of potash per acre. With chemical manures alone the best results were obtained from 6 cwt. superphosphate, 2 cwt. sulphate of ammonia, 2 cwt. sulphate of pot- ash, and 1 cwt. nitrate of soda per acre. The last named was applied as a topdressing when the potatoes were through the ground, just before the first earthing up. These experiments and the results of the writer's own experience show that on all except virgin soils, which naturally contain a large quantity of organic matter, a dressing of from 10 to 15 or 20 tons per acre of organic general manure, such as PROPAGATION 35 farmyard manure, compost heap, seaweed, or green manure, is essential to maintain the very necessary- quantity of humus, and this with a dressing of approved potato manure at the rate of from 6 to 7 cwt. per acre is likely to produce the most satis- factory results on the average soils. As already mentioned, if the grower desires to mix his own chemical manure, the best mixture will be 1 cwt. sulphate of ammonia, 4 cwt. superphosphate, 1 cwt. muriate of potash, or 1£ cwt. sulphate of potash per acre. For garden use the quantities per square rod would be — li cwt. farmyard manure, 1 lb. nitrate of soda, 3 lb. superphosphate, 1 lb. muriate of potash, or 1£ cwt. of farmyard manure and 5 lb. approved potato manure. To get very early crops it might be an advantage to increase the quantities of the chemical manures up to 1 ton of commercial fertiliser per acre. PKOPAGATION. Potatoes are usually propagated by means of sets commonly called seeds. These sets are not true seeds, though they can be, and often are, grown from true seeds when it is desired to obtain new varieties. The potato tuber is an underground stem specially modified for the purpose of storing away starch; and on it, like any other stem, are to be found a terminal bud and several lateral buds situated in the axils of rudimentary leaves. The bud is the eye, and the rudimentary leaf is only a little projection on the lower side of it. Each bud is capable of growing up into a stem on which roots develop and from which a new plant is formed, so that every bud can form a new potato plant. 36 POTATO GROWING This method of propagation from buds or cuttings is called a vegetative method to distinguish it from the true sexual method by means of true seeds. Like all vegetative methods of reproduction, unless the greatest care is taken to propagate from the best types and to maintain the vigour of the varieties, deterioration is sure to set in. Faulty saving of sets and the careless handling of same is the cause of old and well tried varieties be- coming so weakened in time that they become very susceptible to attacks of all kinds of diseases and in the end disappear from our fields and gardens. The old Derwent, at one time a favourite variety in New Zealand, has now disappeared from culti- vation through faulty selection and saving of sets, and its loss is regretted by many. Had care been taken to select immature sets and to treat these in a proper manner, there is every reason to believe that it would have continued to maintain its vigour for a long time. The selection of sets and the careful storing and treating of same, so as to maintain the full vigour of the buds which are to form our new plants, is probably the most important operation in potato growing, and it is the one far too often left to the other man. Every grower ought to know the history of the stock from which his sets were obtained, and instead of purchasing the supplies of sets when the planting season comes round, he ought to obtain them either at digging time or early in the winter, and their preparation should commence then. There are three important points which require attention in the selection and preparation of sets. These are (1) the selection of immature tubers, (2) the greening of the sets, (3) the boxing and sprouting of the sets before planting. PROPAGATION 37 It is now generally recognised by the best growers in England and Scotland that potatoes produce better and heavier crops and are less liable to attacks of disease when they are grown from sets obtained from a colder and moister climate. In England they like Scotch seed, and in the southern parts of Scotland they obtain their supplies from the North or from colder and more backward districts. The only ex- planation of the superiority of seed from colder districts is that the crop never has an opportunity to ripen off properly before the shaws are cut down by the frost; consequently the tubers never have time to mature. The same results can be obtained by digging the crop before the shaws ripen off completely, and this method is followed in Jersey where large quantities of potatoes are grown for the early London market. The Jersey people have prohibited the importation of potatoes of any kind, to prevent the introduction of the destructive wart disease, so that the Islanders have to depend entirely on their own grown sets. Their method of seed selection is as follows. "When the digging is being carried out in July the necessary quantity of sets required for the following season's planting is put aside. Good medium-sized tubers are selected for the purpose. These are spread out in the sun to green, and afterwards stored away in boxes in cool, airy, frost-proof barns. Some of the Ayrshire farmers who grow specially for the early markets also save their sets at the time of digging, what are known as "seconds" being kept back, while others depend on getting their supplies from later and colder districts. In New Zealand, some of the progressive Oamaru growers obtain their sets from Southland every year, and the Oamaru district is famous for its potatoes. 38 POTATO GROWING To show the effect of locality and climate on sets, the following experiment was carried out at the Mosgiel District High School garden by the Agri- cultural instructor for the Otago Education Board. Sets were obtained from both Christchurch and Invercargill of Up-to-dates, and as far as outward appearance went the Christchurch sets looked the better sample, though they were both a good aver- age lot as regards shape, size, and cleanliness. Two plots were set out and treated exactly alike as regards manuring and cultivation, and both crops were dug at the same time. Canterbury sets produced a crop at the rate of 7 tons per acre; Southland sets produced a crop at the rate of 14 tons per acre. It will be seen from this experiment that South- land sets produced a crop exactly double that of the Canterbury sets, and the only explanation is that the Southland sets were grown in a cooler and moist climate which prevented the crops from ripening off properly before the shaws were cut down by the frost, whereas the Canterbury sets would be thoroughly ripened off before they were dug. Were we dealing with true seeds, thorough ripening would be an advantage, but the tubers are not seeds, and the chemical changes which take place when the starch is being stored away in the tubers, if carried out to the fullest degree, seem to retard the rapid shooting and quick development of the buds, when growth commences in the spring. This experiment demonstrates beyond all doubt the advantage of planting immature sets, and though the small aver- age .yield obtained in the Auckland province is no doubt due to digging the crops when green to get them into the early market it also suggests that there is something wrong with the selection or obtaining Good and poor quality potato,seed. The accompanying block represents a fine sample of which Mr. Dobbie, the successful Scottish grower, calls " strong seed." By this term he means tubers for planting, weighing from four to six ounces, or even more. Mr. Dobbie advises cutting strong seed, after it has been sprouted, into two or three divisions as in the illustration, leaving at least two growths on each section. This plan tends to bring about a run of large tubers in the crop. 'Strong Seed." PROPAGATION 39 of sets, and that by obtaining supplies grown in the South the crops could be increased with little or no addition to the cost of cultivation and manuring. It also suggests the advisability of the Canterbury growers getting their supplies from the South, at least every three or four years. In field cultivation, when crops are grown specially for seed, an effort should be made to keep the varieties true to name and type. The crop should be gone through when in flower and any rogues that appear should be either dug out right away or marked with a stick to distinguish them later on when digging takes place. The crop should be dug as soon as the leaves attain their maximum growth and begin to show signs of becoming yellow round the margins, when the flowers wither, and as soon as the skins of the tubers are firm enough to stand a gentle rubbing with the hands. Crops planted about the beginning of October will be ready to dig by the end of February or the begin- ning of March. Of course they will not be fully matured or so heavy as they would be if left to ripen ; but potatoes for seed are usually sold at a much higher rate than ordinary table potatoes, so that it will pay to sacrifice a portion of the yield to obtain a first class sample of seed. Our practice when growing for seed is to dig with the forks taking care not to damage any of the tubers. The latter are thrown out on the dug land as the operation proceeds, and all that are too large for seed are collected and sold as table potatoes. Though these are not properly ripened they will keep quite well when stored in the usual way. The very small ones are also collected and sold for feeding pigs or fowls, while the seed is left on the surface exposed to the sun and air until it is quite green. c 40 POTATO GROWING There is considerable difference of opinion as to the size of sets, but it is generally recognised that tubers about 1J in. to 2 in. wide and weighing from 2 oz. to 3 oz. are the most desirable. To plant larger tubers is a waste of food, and smaller ones cannot be expected to have such strong eyes or buds. After greening, the sets are collected and stored away in airy sheds, or if the climate is not severe, under trees or hedges, until they are boxed. In garden cultivation the best practice is to select the sets for the following season as digging proceeds from day to day to provide the household supplies. This is usually during the months of January and February. Tubers of the desired size are selected from the best plants, that is, those which produce a reasonable number of good ordinary tubers with few or no small ones, and only clean, nicely shaped tubers free from all trace of disease or blemish should be retained. In this way plants which produce only very large tubers or those which produce in addition to a few large ones a lot of small ones are not per- petuated. By following this method of seed selection not only is deterioration prevented, but a marked improvement in the quality and quantity of the potato crop is effected. Another method of seed production is to replant a portion of the ground from which the early crop has been dug with retarded sets. Of course the crop will not have time to mature, but a number of tubers suitable for seed will be produced and they will be immature and only of medium size. Greening the Sets. — After digging, the next oper- ation in proper seed saving is greening. Like every other stem the potato tuber becomes green through its developing the chlorophyll or green colouring PROPAGATION 41 matter when exposed to sunlight. Exposure to light also toughens the skin, the rain washes off the dirt and disease spores, or if the weather is dry the dirt falls off with handling. Darkness and dirt are the most suitable conditions for the comfort and preservation of the spores of the disease, which find suitable shelter in the dirt attached to the tubers, or in the hollows of the eyes, and are ready to commence growth when the next growing season comes round. Sunshine and fresh air are the chief agencies for destroying the spores and keeping disease in check, so that by greening the tubers and storing them where they can have an unlimited supply of fresh air during the winter, any disease spores adhering to them are killed before the following planting season. Greening is usually done by spreading the newly dug tubers out thinly on the surface of the newly dug ground, or if only a few sets are required they can be collected and spread out thinly in boxes under a hedge or fence. Storing and Sprouting. — After greening, the next important operation is the storing of the sets in such a way that they will retain the full vigour of the best buds, and not waste their energies in making premature shoots which have to be rubbed off before planting. The most desirable place to store them is in the open air, and in districts where there is little or no frost they can be spread out on the shady side of a hedge or wall, or placed under the shelter of trees, until they are boxed up. When there is a danger of their being spoiled by frosts they should be placed in a dry, airy, frost- 42 POTATO GROWING proof, light shed or other building, and some arrange- ment should be made whereby there is a constant circulation of fresh air. Some such system of ventil- ation as is recommended for greenhouses, namely bottom ventilators near the ground to admit fresh air and top ventilators near the ridge to let out the foul air would be suitable. The worst conditions under which the sets can be stored is in a warm, muggy, dark cellar or in the ordinary pits or clamps. These conditions not only preserve any disease germs there may be but also encourage the growth of spindly yellow shoots which must be rubbed off before planting. As the new potato plants grow from buds that develop on the outside of the tubers, and there is only one first-class terminal bud on each, if this develops prematurely and has to be rubbed off, it must be from second-class buds that the crop is grown. Though this may be satisfactory it is not the best. To some extent the larger the tuber the stronger the terminal bud, hence the reason why growers of early crops like to plant whole sets of a fair size. A good sized set has a better terminal bud than a small one, though it is often surprising what a strong sprout a little tuber will produce, when it has been properly treated. Generally speaking, when a crop is required in a hurry for the early market, whole sets should be used; when grown for the main crop, and they can have more time to develop, smaller sets or cut ones can be used. Boxing the Sets. — To preserve the terminal bud and to ensure its getting the best supply of sap when growth commences, the tubers are stood up on their ends in sprouting boxes, which are made as follows. PROPAGATION 43 The most useful size is about 27 inches long, 18 inches wide, and 3J inches deep. The sides and ends can be made of £ inch oregon or white pine, and the bottom f inch slats 3 inches wide with a space of about i inch between each to allow moisture to drain away, should they get wet. The uprights and cross pieces should be of deal 1 inch by 2 inches, the former being nailed in the corners and the cross pieces fixed across near the top of them. A strip 1 inch by 2 inches should be nailed across from end to end to keep the end pieces in position, and act as a handle. The corner pieces are from 6 to 7 inches long, and the boxes are so made that they stand on top of one another leaving a clear space of three inches between each layer of sets to admit of a good circulation of fresh air as well as a certain amount of light. Suitable boxes can be made out of old fruit cases which possess the advantage of being light to handle. Such boxes cost about sixpence each. Those made from oregon will probably cost between three and four shilling's, but they last a long time if they are stored away in a dry shed or under the shelter of a dense evergreen tree when not in use. There is no doubt as to the wisdom of placing the tubers in sprouting boxes. It might be stated by many as the excuse for not adopting this method of seed storing that it is a lot of labour packing them all up on their ends. In reality it is less laborious than storing them in heaps or in sacks and turning and picking them over from time to time. When the seed boxes are filled, either immediately after digging or from time to time during the winter to provide inside work for the men on wet days, they require no further attention until planting time. When setting the tubers up care has to be taken 44 POTATO GROWING to place them with the bud end uppermost. In autumn and early winter when the eyes are dormant there is little to distinguish one end from the other, but there is usually a little piece of stalk to indicate where the tuber was attached to the parent plant, and the tubers should be stood on this. My own practice is to pack up the tubers in boxes from time to time when I have to provide work for the men on wet days, and to stand these boxes out- side in the shelter of a wall and to leave them there all the winter. Though greened tubers will stand a few degrees of frost, it is not safe to take too great risks. I accordingly tack some old bags or pieces of oilcloth over the top boxes during the most severe winter months. When there is danger of frost, the boxes can be stored in dry, airy, frost-proof sheds, and when all danger of frost is over they can be carried outside to harden the sets up and to prevent their producing long spindly shoots. It will be seen, therefore, that not only is boxing the sets the correct thing from a cultural point of view, but it is also the least troublesome and conse- quently the least expensive. When they are stored in sacks or heaps they have to be picked over from time to time, and the result is, the best bud goes at the first picking, the second best bud is rubbed out at the second picking, so that when sets are twice picked the third best bud is left to form the new potato plant, and the crop is third rate. The most progressive growers in England and Scotland attach great importance to boxing the sets, and it is reported that one grower in Lincolnshire has three large glass houses built like greenhouses, with both top and bottom ventilation, in which he stores his boxed sets during the winter. They are PROPAGATION 45 then safe from frost and still have light and fresh air. The three greenhouses can hold 1,000 tons of sets, and he says that no matter how perfect every condition of potato cultivation is, if the stock of sets is not of high germinating power, free from disease, and planted whole, the grower cannot hope to obtain the best results. In Ayrshire, the growers store their boxed sets in large barns which are well ventilated both top and bottom to secure a through draught. In the spring, after all danger of frost is over, these boxes can be stacked outside in the shade in order to firm up the sprouts and to prevent them from becoming spindly. By planting sprouted sets the crop will be ready to dig three weeks to a month earlier than if the sets had been unsprouted. Some of the advantages of planting sprouted sets are: — (1) A few weeks' growth is secured in the boxes before planting has to take place. (2) If both sprouted and unsprouted sets are planted about the same time the crop from the sprouted sets will be ready to dig several weeks before the unsprouted sets. (3) If the spring be cold and backward and the soil wet, planting can be delayed for a few weeks. (4) On freshly tilled land the sprouted sets get growing at once, and make such rapid growth that they smother the weeds. (5) By planting sprouted sets each will grow into a plant, so that there is no danger of blanks. (6) The sets are clean and free from disease spores through having been stored in the open air and sun- light. (7) By retarding the growth of the buds until the proper season, and thereby retaining the best and most vigorous ones, the plants are more vigorous and less liable to be attacked by disease and are certain to produce a larger crop. 46 POTATO GROWING Propagation by Meang of Cut Tubers. Until a few years ago it was the usual practice to cut the tubers for sets, and this is still quite a good plan to adopt for the main crop when there is no great hurry to get them dug early, and when large tubers suitable for table use have to be used. When the tubers are boxed and stood on their ends, the top bud sprouts first, and there is a great difference between it and those lower down. The latter are all at about the same stage of development and of the same strength, so that by cutting the tubers lengthwise we get pieces with at least two good buds on each, and these when planted will produce an even crop. Round-shaped tubers do not show the same vari- ation in the strength of the buds as kidney-shaped ones, and cutting of the tubers is more satisfactory. Tubers intended to be cut should be stored in the open air or a light frost-proof shed, as recommended for whole sets, to retard growth and retain the full vigour of the buds. They should be cut lengthwise with a clean sharp knife into two or three pieces each with one or two good buds. Cutting should be done just before planting. It is a mistake to cut tubers and leave them spread out to dry and shrivel up. It is a good plan to dip the cut surface in powdered quicklime or powdered charcoal, or in a mixture of two parts flowers of sulphur and one part slaked lime, as this prevents the spores of fungus from attacking them and causing decay before the eyes have had time to shoot out and form new roots. Propagation by Means of Single Eyes. When it is desired to increase scarce and expensive varieties they are often grown from single eyes, but Potato seed that has been over-sprouted. Potatoes showing how the roots arise from the base of the shoot and not from the tuber. PROPAGATION 47 as it has already been explained that the strength of the buds varies according to the position they occupy on the tuber, this method is not one which can be recommended to secure an even crop. It should be practised only for some special reason, such as the rapid propagation of seed tubers of some new variety. The tubers should be stored in the usual way, and in the spring they can be cut up into as many portions as possess eyes, the cut surfaces being dipped in lime or the mixture of lime and sulphur already recommended to prevent rapid decay. They should be planted in the usual way, except that they require less room in the drills. When potatoes were scarce and expensive, a method was adopted in some countries to retain the bulk of the tuber for food and to grow the new plants from the eyes with a piece of the skin attached The eyes were cut out with a disc of skin of about the size of a shilling and about an eight of an inch thick. The cut surface was dipped in the lime and sulphur mix- ture and they were then planted in boxes of fine light soil at a distance of two inches apart, the bud being covered with about half an inch of soil. The boxes were placed in a greenhouse or frame, and when the shoots appeared above the soil they were gradually hardened off and fully exposed to the light to prevent their becoming drawn and spindly. "When well rooted and all danger of frost had passed, the plants were lifted carefully with the soil adhering to the roots and planted out at the usual distance apart. A few branches or pieces of scrub stuck in round the newly put out plants would protect tnem from the cold winds until they got established. It will be understood that when the tubers are intended for food it would not do to expose them 48 POTATO GEOWING to the light or they would soon become green and consequently unfit to eat. Propagation by Means of Cuttings. The method of growing plants from cuttings is also practised when it is desired to increase a variety rapidly, and during the potato boom it was exten- sively carried out. The whole tubers are placed on their sides in boxes, just covered with leafmould or some light soil, and then removed to a heated greenhouse or frame to start growth. When the shoots are about an inch or an inch and a half long they are detached from the old tuber and planted out in boxes of light soil composed of loam one part, leafmould one part, and clean sharp sand one part. They are set like ordinary cuttings, about two inches apart. The boxes are placed in the heated greenhouse or frame and shaded for a few days until the plants take to the new soil. They are then given more light to prevent their becoming drawn and spindly, and afterwards gradu- ally hardened off in preparation for planting out when all danger of frost has passed. The soil for plants grown from either cuttings or eyes would require to be in a finer state of cultivation than for planting ordinary sets, and it would be an advantage to plant in shallow drills about two inches deep. When the cuttings are being planted out they should be lifted from the boxes with as much soil adhering to their roots as possible. They should be set about two to three inches deep with the growing point of the stem just above the ground, and should be sheltered with small branches for a few days. These methods of intense propagation are not recommended for use except under exceptional cir- PROPAGATION 49 cumstances, for the loss of vigour and the rapid dete- rioration of many of the boomed varieties was no doubt due to this method of over-propagation, which makes use of weak and unsuitable buds to raise new plants instead of following the usual practice of growing only from the best and strongest. Though it is usually considered that any plant when propagated in a vegetative manner for some time will deteriorate, this deterioration could be very considerably reduced by sensible methods of saving and selecting the seeds or sets from which the new plants are to be grown. A little attention to the details recommended, such as the selection of im- mature sets, the greening and storing of some to prevent premature sprouting, and the planting of whole sets of a reasonable size, properly sprouted, with a limited number of buds on each, would greatly increase the health of the plants and mean a con- siderable increase of the crop with little extra outlay. To sum up, the essentials of up-to-date propagation are: — (1) Select immature medium-sized sets in autumn. (2) Green sets by exposure to sunlight in autumn. (3) Store sets in cool, dry, frost-proof shelter during winter. (4) Sprout the sets in a warm, light, airy spot in the spring. (5) Plant whole sets. Raising New Varieties of Potatoes from True Seeds. "When growers wish to obtain new varieties of potatoes which will be better in flavour, stronger in resisting disease, better in shape, earlier or heavier 50 POTATO GROWING croppers than those already in cultivation, they resort to raising them from true seeds. These seeds are the result of the fertilisation of the flowers either in a natural way through bees or other insects distributing the pollen, or in the usual way adopted by hybridists, namely hand-pollination. The flowers of the potato are complete, that is they have in addition to the calyx and corolla both stamens and pistils in the same flowers, the one producing the pollen and the other the seeds. It is often difficult to get potatoes to produce flowers at all, and when they are grown in the ordinary way for the production of tubers either they fail to produce flowers or those which they do produce are incomplete and incapable of producing seeds. Hybridists have often to grow their seed-producing varieties in pots in the greenhouse, or they plant them on poor dry soil in a sunny position where the growth of the shaws is less rank. In addition to the difficulty of obtaining flowers there is also further difficulty in obtaining pollen when the stigmas are in a receptive condition. To get the best results and to follow up the raising of seedlings in a scientific manner it is necessary to have everything under control, and for the operator to exclude bees and other insects which may upset his work by introducing undesirable pollen. It is the exception rather than the rule for the flowers to be self-fertilised, but to make quite sure it would be better to remove the anthers from the flowers to be pollinated before they have burst. This is easily done with a pair of forceps or tweezers, and after emasculating the flowers they should be tied up in muslin bags if they are growing outside where bees have access to them. In the greenhouse the PROPAGATION 51 insects can be excluded by covering the ventilators with muslin until the stigmas are ready. The flowers have to be examined from time to time with a hand lens to determine when the pollen grains are right and when the stigmas are in a receptive condition. They are sticky when they are ready to receive the pollen. Pollen should be obtained from clean, healthy, well-grown plants, and should be well developed and collected from flowers whose anthers have just burst. Select good, well-developed pollen grains, and with a small, clean camel hair brush pick them up and transfer them to stigmas of the varieties to be operated on, the covering being replaced and kept on for a few days until the flowers wither. The transferring of the pollen from the stamens of one variety to the stigmas of another is called pollination, the union between the pollen grain and the ovule being called cross-fertilisation. Great care has to be taken to prevent the pollen grains from being damaged in any way when they are being transferred, and likewise the stigma has to be treated very gently to prevent its being damaged. As soon as fertilisation has taken place the ovary with the little rudimentary ovules begins to increase in size and the ovules develop into seeds. When the potato apples are ripe they are collected and stored in a warm, light, and sunny place until they begin to decay or shrivel. They are then bruised in water and washed in a fine sieve until all the pulp is removed. The seeds are then spread out in a warm position until they are dry, and stored away in a cool position until the following spring. 52 POTATO GROWING Sowing the Seeds. — Sowing can be done either in boxes or in seed pans. These should have a layer of rough stuff placed in the bottom for drainage and over it a layer of moss, leaves, or the riddlings out of the loam. Fill the boxes or pans to within an inch of the top with the ordinary soil and then place a layer of fine soil on the surface to provide a smooth seed bed. A good mixture contains two parts loam, one part leaf-mould, and half a part sharp, clean sand. Make the bed firm with a levelling tool and sow the seeds thinly and evenly, pressing them into the soil and dusting a quarter of an inch of topping soil over them as a covering. Water, and remove to a warm greenhouse if one is available; if not, put in a cold frame, or cover with a few sheets of glass. Even when the boxes or pans are placed in a greenhouse they are better covered with glass to retain moisture until ger- mination takes place. To prevent the growth of lichens or moss the soil is often sterilised before sowing the seeds, either by baking it or by scalding it with boiling water. As soon as the seedlings appear they should be placed near the light to prevent them from becoming drawn and spindly, and when they are large enough they may be pricked out into boxes of soil similar to that recommended for seed sowing, the little plants being placed about two inches apart to give them room to develop. When growing well they may be transplanted again into boxes giving them more room or they may be potted up into five-inch pots using a similar soil to that already recommended with the addition of a little bone meal and well decayed manure. Place the newly potted or boxed plants on a shelf in the greenhouse near the glass until they take to the new soil, and provide stakes for those that require them. PROPAGATION 53 They should next be placed out in a frame to harden them off in preparation for planting out. The sashes will be kept fairly close at first, but later on they will be opened up during the day and when the weather is warm removed altogether. "When all danger of frost is over the plants can be planted out on a warm, well-drained, fairly rich border, allowing a distance of 18 inches between the rows and a similar distance between the plants in the rows. Those growing in boxes would require to be carefully lifted with a ball of soil attached to the roots, and it is to avoid injury to the roots when planting out that they are often grown in pots. As a protection from cold, cutting winds, it is wise to place a few pieces of scrub or branches round each plant until it is properly established. To obtain the best results it is necessary to keep the plants grow- ing without a check from the time the seed germinates until they are planted out. Seed sowing is sometimes done in the open, a warm sunny border well sheltered from the cold winds being selected. Make the soil fine, and if it is at all heavy mix in some sand and leaf- mould. Sow the seed two or three inches apart and about half an inch or less in depth in drills six inches apart. Cover them with fine soil and make the sur- face firm. To retain moisture and provide a little shade and shelter, place some branches of manuka over the seed beds until the seedlings appear. When they are about two or three inches high the young plants may be lifted carefully and planted out in their permanent position, shelter and shade again being provided by means of pieces of scrub until they are established. The advantage of inside over outside sowing is that the plants are started earlier and hence 54 POTATO GROWING have a longer period of growth. They consequently form better and bigger tubers by the end of the season. During the summer weeding will have to be attended to regularly. The surface soil should be kept cultivated and a slight earthing up to steady the shaws will be an advantage. By the end of the season small tubers will have been formed, and these are stored away in boxes of dry sand in a cool, frost-proof shed until the following planting season when they are planted out and treated like ordinary potatoes. Only those of good shape and cropping ability need be selected for further cultivation, but as it takes several years to fix a new variety it is not desirable to place new varieties on the market too soon. When crossing the different varieties records should be kept of those used to provide the pollen and to produce the seeds, and the whole operation should be carried out in a careful and scientific manner. As explained at the commencement of this chapter the aim of the raiser of new varieties is to produce kinds superior to those at present in cultivation in one or other of the following respects : — (1) They should be as far as possible disease- resisting. (2) They should be of a good shape, with shallow eyes. (3) They should be good croppers. (4) They should have good flavour and should cook well. It may not be possible to combine all these good qualities in one variety, but they provide the standard to be aimed at. • - - ' '-■ ^ ;-*/-*'- . ^SiRsKr ■ (UffijHHK^ a - -. J ■ ' JiJ* r .**' V*4 » x ■ Planting potatoes with dibber See page 59. Planting in shallow drills. See page 60 GARDEN CULTIVATION 55 POTATO GROWING IN THE VEGETABLE GARDEN. Preparation of the Soil. — In a well ordered vegetable garden, one portion, probably about a fourth or fifth of the cropping area, is trenched every year and in this all the vegetable refuse and compost heap are buried. Trenching should be done in the autumn or early winter as this gives plenty of time for manure to decay and for the thorough weathering of the newly- dug soil. The operation consists of turning over the soil to a depth of about two feet to two feet six inches, and may be described as follows : — 1. Take out a trench two feet wide and two feet deep as an opening and wheel this over to the other side of the plot to be operated on. Then break up the subsoil in the bottom of the trench with a fork or pick. 2. On the top of the loose soil in the bottom of the trench place a good layer of compost heap or vegetable refuse. 3. Throw over the top spit of soil on to the vegetable refuse, and shovel over the crumbly part on top of it. 4. Spread a layer of strawy farmyard manure or compost heap on top of the crumbly part. 5. Throw over the second spit on top of the manure or vegetable matter, and again throw the crumbly part left in the trench on top of it. 6. Break up the subsoil in the bottom of the trench with a fork or pick. D 56 POTATO GROWING 7. Mark off another two feet and continue the operation right across leaving the surface as rough as possible. In some cases where the soil is stiff it is made up in ridges to expose a greater surface. This will completely invert the soil to a depth of two feet ; it will also open up and enrich the subsoil by the addition of manure and organic matter. CFI D G J. E H K Bastard Trenching. BASTARD TRENCHING.* Divide plot in two equal parts, A and B. Dig C and remove to X. Loosen and manure spit D but do not remove. Shift E to C. Loosen F. Shift G to E. Loosen H., etc. Work to end of A, then top spit K will fill in J. At finish the soil at X will fill space left at Y. True Trenching. TRUE TRENCHING. Remove soil C to X. Remove subsoil D to T. Loosen and manure but do not remove subsoil E. Shift soil F to D. And subsoil G to C. Loosen and manure H. Shift I to G. And subsoil J to F, etc. Note, that soil and subsoil will then have changed places. The benefits derived from trenching are as follows: 1. The rooting medium is deepened and the root run increased. 2. Air and other agencies which render the inert and insoluble substances in the soil soluble and avail- •See Council & Hadfield's " Agriculture," pages 228-229. GARDEN CULTIVATION 57 able to plants are able to get to work and greatly increase the supplies of food for the crops. 3. By adding compost heap and strawy farmyard manure we increase the organic matter, which has an important influence on the texture of the soils, binding together sands and opening up clays. 4. Drainage is assisted, for when rain falls it per- colates down into the subsoil and is there carried away in the pipes provided, or it sinks into the sub- soil if that should be gravel or sand. 5. Trenched soils also hold moisture betteis than those not well cultivated, and as both the rooting medium and the water-holding capacity of the soil are increased plants suffer less from lack of moisture during dry weather. 6. "Well trenched soils admit fresh air which is essential for the healthy development of the roots, and being well drained they are warmer and the crops consequently mature earlier. 7. Trenched ground is easy to cultivate afterwards, even women and children having no difficulty in carrying out the usual cultural operations connected with potato growing when the soil has been well trenched to begin with. If the soil is hard and lumpy, due to improper preparation, subsequent cultivation becomes laborious. The benefits derived from trenching are tremen- dous, and when one has only a small garden it should be trenched, not only to bring it into a condition favourable for the production of maximum crops, but to maintain its productiveness. By treating a fourth of the garden each year the whole garden is trenched over every fours years, and as a little of the loosened subsoil is brought to the surface each time, the depth of good soil is gradually increased. 58 POTATO GROWING When the top layer of good soil is not more than a foot deep and the subsoil is either sand or clay which it is not desirable to bring to the surface, what is known as bastard trenching has to be resorted to.* Bastard trenching increases the depth of the soil and has many of the advantages of proper trenching, and by continuing from year to year, each year oper- ating on a fourth of the garden and bringing up a little of the improved subsoil, the depth of good cultivated and manured soil is gradually increased. Digging. — This consists of inverting the soil to a depth of one spit, and if necessary burying in a good dressing of farmyard manure. Digging should be done in the autumn or early winter, and the soil left as rough as possible to expose the maximum surface to the disintegrating influences of frost, air, and sunshine. Trenching has been described at some length because the potato is the most suitable crop for newly trenched ground, or for land that has been brought into cultivation for the first time. When a new garden is being formed the greater part of it should be cropped with potatoes the first year. The cultivation necessary for the potato crop improves the texture of the soil, the weeding and the luxuriant growth of shaws keep the land clean, and the crop is dug sufficiently early in the autumn to enable grass to be sown and shrubbery and flower beds and borders prepared for planting. Preparation of the Land in Spring. As soon as the land is dry enough it should be forked over and all lumps broken, but care should be taken not to •See Diagram. GARDEN CULTIVATION 59 bury the fine soil formed "through the agencies of frost, etc., during the winter. After forking, a dusting of crushed agricultural lime should he given, and wood ashes or an approved fertiliser may also be sown on the surface and worked in with a manure drag or steel rake when the surface is being levelled and the lumps broken. Planting. — There are three methods of planting worthy of the cultivator 's attention. Any of them will be found suitable on some lands, but when the sets are sprouted and the soil well cultivated planting with the trowel will be found the quickest and best. (1) Planting with a Dibber. — This is an old- fashioned method and quite suitable for light soils. If the soil is heavy and at all wet a hard surface is formed inside the hole through which the roots have a difficulty in penetrating, and if the soil is very dry or lumpy the holes fill when the dibber is with- drawn. A dibber consists of a piece of hard wood three inches by three inches and about three to four feet long, the lower end being blunt and rounded so that it will make a hole about two inches wide, and there is a piece of wood nailed on four inches from the end to regulate the depth of the holes. In addition to regulating the depth of the holes the cross-piece acts as a tread, and the distance it projects on one side can be the distance at which the sets are planted, so that while the dibber makes one hole it marks the position of the next, thereby securing even planting. It will be necessary, of course, to mark off the position of the rows with pegs at each end of the plot, to stretch the line tightly between the pegs and to make the holes close to the line to secure straight rows. A child can drop the sets into the holes with the sprouted end up, and the covering can be done by 60 POTATO GROWING drawing in a little loose soil over the set with the manure drag or iron rake. When possible, avoid planting with a dibber. It is a lazy method in any case, and is fraught with grave danger, since, unless the utmost care be taken, the sets will remain suspended halfway down the hole, in which water may accumulate and cause the tubers to rot and die. (2) The most popular way of planting potatoes in the garden is to measure off the distances between the rows at each end of the plot and to put in pegs, then to stretch the line between the pegs, and with an ordinary draw hoe or a special triangular hoe to take out a drill about three or four inches deep. The sets are then planted directly from the boxes to the drill at the necessary distance apart. Chemical manure, either superphosphate and potash or bone meal, or an approved potato manure is sown in the drill on top of the sets, and the soil pushed back with the feet or drawn into the drill with the manure drag or rake. The pegs should be left at the ends of the plot to mark the position of each drill, and a good strong label with the name of the variety and the date of planting placed to each variety. When the soil is lumpy or turfy and not very well prepared, it is easier to make the drills with a spade. The soil from the first row is removed to the other side of the plot to be used for filling the last drill, and if the soil is poor the trench may be made six inches deep and a layer of leaf -mould or compost heap two inches thick placed in the bottom of it. Farmyard manure may also be applied now if it was not possible to dig it in earlier, but it is considered that it affects the flavour of the potatoes and en- courages a rapid soft growth of shaws which are GARDEN CULTIVATION 61 very liable to be attacked by disease. It is better, however, to apply the farmyard manure at planting time than not to apply it at all. The sets may be planted directly from the boxes to the drills at the desired distance apart, and the soil from the second row used to cover the sets in the first. This process is continued right across the plot and the last drill filled with the soil deposited there for that purpose. Though the method of planting in drills is a good one, it seems a waste of energy to open a drill the full length of the plot to plant sets at from fourteen to sixteen inches apart, and to push the soil all back again. (3) "When the soil is well prepared in the first place and the sets well sprouted it is both quicker and better to plant with the trowel. The rows are marked off as already recommended and the line stretched between the pegs. The trowel is pushed down beside the line to a depth of four inches, then pulled forward and the set lifted from the box and dropped in behind the trowel, sprout end upwards, and with a few pushes with the point of the trowel or the foot the hole is filled up. Though there is very little danger of the sprouts on the sets being broken off (when they are formed in the open and are short and sturdy) either when planting with the dibber, or in drills, there certainly is less danger when planting with the trowel. When the sprouts have been forced by placing the sets in a heated greenhouse, planting with the trowel is certainly the most desirable. In every case when sprouted sets are being planted they should be put direct from the box into the holes or drills. Properly made potato boxes should have a strip of wood across the top to serve as a handle, and as light wood should be used in their construction, 62 POTATO GROWING even when full of sets they are not heavy to carry about. Potatoes are often affected with scab when grown in sour soils, and though, being only a skin disease, it does not detroy the tubers, it looks bad, and lowers their selling value. It can be avoided by preparing drills with the spade as already described and placing a layer of pine needles or clean straw in them on which the sets are planted. The straw prevents the sour soil from coming into contact with the new tubers, and they come out clean and sound when dug. After planting, the potato patch should be level. It is a mistake to draw the soil up into ridges until the earthing up is required later on. "When the farmer is covering his potatoes with a plough he has to leave ridges, but there is no reason whatever for reproducing these ridges in the garden, unless the ground is very wet and sour. After Cultivation. — As soon as the sprouts appear above the ground it should be stirred and cultivated either with the scuffle hoe or the manure drag. This stirring and working of the surface destroys quanti- ties of weeds in their infancy, admits fresh air. keeps the soil warmer, and prevents loss of moisture during dry weather. There is often a danger of very early crops being seriously damaged by late frosts, and as a precaution a little strawy litter may be spread between the rows and drawn over the young plants when danger appears, or a couple of little twiggy branches may be stuck in on the sunny side of each until all danger is over. It is in thawing rather than freezing that damage is done to the tender leaves, and by shading them from the morning sun the GARDEN CULTIVATION 63 thawing takes place gradually and the leaf tissue is not destroyed. Watering lightly frosted plants overhead with cold water before the sun gets on to them is also recom- mended and is well worth trying, for though the frost will not destroy the plants entirely it gives them a severe set-back and delays their development. When the stems are from four to six inches high the soil between the rows should be forked or broken up with the manure drag and made fine in prepar- ation for the first earthing-up. The first spraying will also be given now, but this will be described fully in another chapter when dealing with disease. The earthing-up should be done when the soil is dry. It should be pulled up with the hoe under the leaves not over them, and the top of the ridge need not be made at all sharp. In fact, a flat topped ridge is better for catching the rain in very dry weather. Later on, when the stems are about nine inches high and the leaves are almost meeting across from ridge to ridge, there may be a second and final earthing-up, the ridges being made as high and pointed as possible. The first earthing-up is given to steady the stems and cultivate the soil, the second to cover up the young tubers and prevent them from becoming green and unfit for food. It has been suggested that the pointed ridges run off the super- fluous rain, and that the disease spores instead of being washed down to the tubers are washed down between the ridges where they can do no harm. The deep covering of soil would no doubt filter the moisture to some extent and remove some of the disease spores, but anyone who left potatoes in the ground after the shaws had been destroyed by disease would be courting failure. When the shaws meet across from ridge to ridge and completely cover 64 POTATO GROWING the soil there is little danger of weeds getting through, but if any appear they should be pulled up before they have a chance to seed. Digging the crop. — If a full crop is desired, digging should not commence until the growth of the shaws has been completed and the flowers have dropped off; but as potatoes are scarce and dear during November and December it is often desirable to commence digging the early varieties as soon as the tubers are as large as pigeons' eggs. The digging of the second early kinds, and in fact the main crop, may be undertaken as soon as the leaves begin to turn yellow and the skins of the tubers cannot be rubbed off with the fingers. The difference between early, second early, and main crop varieties is simply one of the time which each takes to develop its shaws and its tubers. An early variety does not develop very strong shaws, and a limited crop of tubers is also formed early, so that the sets can be planted fairly close together. A second early variety grows more shaws than an early variety and takes longer to form its tubers. The crop is heavier, and it matures in from three weeks to a month later than a first early. A main crop variety requires a longer period to develop its shaws, which grow far stronger than either of the early kinds. It forms more tubers and these are larger; consequently the ultimate crop may be twice as heavy as that of an early kind. It will be seen, therefore, that to get the best out of the potato patch, only a very limited area should be planted in early kinds, a slightly larger area in second early ones, and the main planting should be main crop varieties. Many growers cultivate only main crops, even to provide the first earlies, as by GARDEN CULTIVATION 65 sprouting them before planting and planting early- there will be tubers fit to dig in four months. Then if they are not required for early digging they can be left to mature their crop which will be far more satisfactory than either a first or second early. It certainly seems a mistake for many growers to plant their limited potato patch with varieties which will produce only half a crop. Digging has to be done carefully, otherwise many of the largest tubers are pierced and damaged. The fork, which should be one with flat tines, should be pushed into the side of the ridges below the tubers, and with the assistance of a pull from the shaws the whole plant, soil, and tubers are thrown forward on to the cleaned and dug ground. At the same time the shaws are shaken and the tubers fall off. Potatoes dug for the early market before the skins have become tough and firm have to be handled very carefully. They are usually packed in old fruit cases when sent to the market, which prevents the skins from being rubbed and the sample thereby rendered less attractive to the buyer. In the private garden only enough for each day's requirements should be dug at one time, and in the market garden only enough for one or two days; for they readily shrivel and become yellow when exposed to the light. The main crop may be dug as soon as the develop- ment of the shaws ceases and the skins are firm. It is not necessary to wait until the tops die down. Digging should be done during dry weather so that the tubers will come out clean, and they may be spread out as they are dug for a day to dry before they are stored away. The large or table tubers may be collected and stored away in a dry, dark cellar or a dry shed, provided they are covered over with sacks or straw 66 POTATO GROWING to prevent them from becoming green. If neither shed nor cellar is available, they may be stored in pits or clamps in the same way as the field crops. The second size should be collected and spread out in the sun to green for seed, and the small ones sold for feeding fowls or pigs. It should hardly be necessary to draw attention to the need for throwing out all tubers showing any signs of disease and those which are damaged by grubs and wire worms ; also to recommend the grower to place all those which have become partly greened through insufficient earthing-up, among the seed. Planting 1 in Lazy Beds. — This method of planting is usually resorted to when the land is wet and boggy or when there is not sufficient time to bring new grass land into a suitable state of cultivation in the spring. The beds are marked off either four or six feet wide, with an alleyway two feet wide between each bed to provide a path and drainage. The surface soil is dug over and the soil from the alleyways dug out to a depth of a foot to eighteen inches and thrown on to the bed to increase the depth of cultivated soil. The sets are planted in rows across the beds. They require less room than those growing on properly prepared and properly cultivated soil, as their shaws never develop to the same extent. Twelve inches between the sets and two feet between the rows should be quite sufficient room. If the ground is covered with a lot of rough grass or weeds which it would be difficult to bury, it would be better to chip the surface and burn the weeds and grass, afterwards scattering the ashes over the dug land. FARM CULTIVATION 67 FARM CULTIVATION. The potato is an important farm crop, and the statistics issued by the Government Statistician for 1918 showed that in all there were 25,502 acres of potatoes grown in the Dominion, distributed as follows : — Yield Acres. Tons. Auckland 3,020 10,915 Hawke's Bay 923 4,231 Taranaki 399 1,558 Wellington . 2,398 12,917 Nelson 486 1,804 Marlborough 361 1,476 Westland 41 166 Canterbury . 12,781 68,106 Otago . 3,508 19,372 Southland . 1,594 10,262 Total for the Dominion 25,502 130,807 The average crop for the principal potato growing Provinces is — Auckland, 3-3 tons per acre; "Welling- ton, 5 -4 tons per acre ; Canterbury, 5 -3 tons per acre ; Otago, 5-5 tons per acre; and Southland, 6 tons per acre. The average crops for the United Kingdom are — England, 5 -84 tons per acre ; Scotland, 5 -90 tons per acre ; Ireland, 3 -83 tons per acre ; and Wales, 5 -36 tons per acre. Prom the above statistics it will be seen that the average crop in New Zealand is nearly the same as the average crop for the United Kingdom, but it is far below what it might be with better methods of seed selection and cultivation. 68 POTATO GROWING The methods which I am going to describe for farm cultivation may not be those usually followed in some of the potato growing districts of New Zealand, but they are more or less those followed by the Ayrshire farmers in Scotland, and there potatoes are probably as well grown as anywhere. The methods have also been put into practice at the Gardens in Dunedin and found perfectly successful, even in seasons when blight has inflicted enormous damage to other potato crops. Preparation of the Land. — As already noted, potatoes do very well on newly broken up pasture land, newly cleared bush land, or that which has been covered with manuka scrub, gorse, or broom. In preparing either newly cleared scrub land or pasture it is advisable to throw over two furrows when ploughing. The top furrow about six inches deep is thrown in the bottom and another furrow thrown on top of it. This ensures a good six inches of clean soil free from weeds and grass roots, and the grass is completely covered up in the bottom where it will gradually decay, and supply the potato plant with food. If ploughing can be done in the autumn, and the top soil left rough, exposing the maximum of surface to the action of frost, air, and rain, it will crumble away, forming a fine tilth which will not require much working to bring it into a suitable state for planting in the spring. Land which has already been cropped with potatoes, wheat, oats, or other field crops, should be ploughed deeply in the autumn, and if farmyard manure is to be applied this should be spread on the surface and ploughed in. At one time it was the practice to spread the farmyard manure in the bottom of the drills when planting in the spring, but this is dis- FARM CULTIVATION 69 continued by the best growers. By ploughing in the manure in the autumn it becomes thoroughly incor- porated with the soil, and is ready to be taken up by the potato crop when growth commences. If the soil is very tough it may be necessary to cross plough it in the spring, then to disc it thoroughly to break up the clods, harrow it well to shake out all the weeds and grass roots, which if abundant should be collected and burned, then finally to cultivate and harrow again before drawing the drills. If the weather is dry and the land lumpy rolling with a Cambridge roller will be an advantage. Potato land should be thoroughly cultivated before planting. Good soil preparation will save a lot of labour in weeding and cultivating later on, and in the spring and early summer many of the annual weeds are destroyed as they germinate. Potatoes dislike hard, lumpy soil, and it is im- possible to get good crops from badly or imperfectly prepared land. The effects of lime in soil-prepar- ation have already been considered. (See page 32). Planting. — The planting season will vary accord- ing to the district and the purpose for which the crops are grown. The determining factor is the late frosts. In a district or position where there is little danger, planting can be done about the begin- ning of August, but if sprouted sets are used it can be delayed for nearly a month and the crop will be ready just as soon. There is a great temptation to get potatoes ready for the market during November and December when prices are good, anchwhen there is a chance of getting another crop off the same piece of ground. Main crop potatoes can be planted any time during October or even in November, but it is usually an 70 POTATO GROWING advantage to get the crop in as soon as the soil is in good working condition. On the other hand, if the weather is at all wet it is better to delay planting until the conditions are favourable. By planting early the crop has the advantage of the good growing weather we usually have in early summer, and the plants develop rapidly and begin to ripen off by the end of January or the beginning of February. The weather at this season is usually very favourable for digging, and even if the shaws have not ripened down, if the skins of the tubers are firm digging can be carried out. We often get rains in early autumn which cause partly ripened potatoes to make a second growth. This spoils the tubers for table use, and if there is warm, muggy weather disease is sure to make its appearance. When the soil has been thoroughly cultivated and is in good working order, the drills are usually drawn with a double mould-board plough, carrying an attachment which marks off the position of the follow- ing drill. This enables the worker to draw neat, straight drills which look better and are much easier to cultivate later on than carelessly drawn, crooked drills. When the farmyard manure has been ploughed in in autumn a drill six inches deep is quite enough, but if the manure is spread in the bottom of the drills they will have to be a little deeper. When, the soil is a bit rough the drills are often drawn with a single furrow plough, but this does not make such a satisfactory job as the double mould-board plough; and it is much better to have proper implements, if the extent of the oper- ations warrants it. If the sets are sprouted the boxes should be carted out to the paddock and the sets planted direct from Breaking up rough bush land for potatoes. A potato planter at work. See page 86 FARM CULTIVATION 71 them, for though the sprouts are green and not easily damaged the less handling they have the better. If the sets are not sprouted they can be carted out in sacks and these distributed along the drills so that the planters have but a short distance to go to replenish their aprons. Early varieties are usually planted in drills 27 inches apart, and the sets are placed from 12 to 14 inches apart in the drill. Later or main crop varieties are planted from 14 to 16 inches apart in the drills, and if the soil is good, these are 30 inches apart. At the time of planting a dressing of some approved potato fertiliser should be sown in the drills. The quantities recommended will be found in the chapter on Manures. After Cultivation. — About a fortnight after planting, the ridges should be harrowed down, eitber with the ordinary harrows turned upside down to pre- vent the tines from pulling out the sets, or with special saddle harrows which fit over the drills. If the soil is not too well cultivated before planting and weeds begin to appear, the cutivator should be run between the ridges, and then they can be set up again with the plough, to be harrowed down again with the saddle harrows, and left until the plants appear. This constant stirring of the soil breaks up lumps, shakes out grassy weeds, destroys the seedlings of annual weeds just as they begin to appear, and by keeping the surface loose any crust which may be formed as the result of heavy rains is broken and air admitted. After the plants are well through the ground they will require to be weeded with the hand hoe, but to reduce the area requiring hoeing the cultivator can be run between the ridges. If it is intended to spray the crop twice the first spraying can be given about 72 POTATO GROWING a fortnight after the hand-hoeing and weeding is completed. The first earthing-up is the next oper- ation, and for it the double mould-board plough or the cultivator attachment will be used. Before the shaws meet from ridge to ridge the drills should be cultivated, the second spraying should be given, and then the final earthing-up can be done, the ridges being thrown up high for the reasons already given. When the shaws meet completely over the drills and cover the entire surface, weeds have little chance, and any strong annual kinds which come through them are easily pulled out. Digging. — The operation already described for digging garden potatoes applies equally to the digging of early varieties in the field. The harvesting of the main crop, however, usually demands the use of labour-saving machinery. After the shaws have died down the ridges can be split with the double mould-board plough, which throws the tubers out on each side and saves a lot of digging, and if the ground is harrowed afterwards and picking again done care- fully very few tubers are lost. There are several mechanical diggers on the market, all of which have some advantages. One throws the tubers out on the dug ground where they are easily gathered, another spreads them out on the soil behind it, and some such device is well worth adopting where potatoes are cultivated on a large scale. If the weather is dry the tubers are often left on the surface to dry for a day, and when collected they are sorted into three sizes: small or diseased ones for pig feeding, second size for the following year's sets, if it is considered wise to save your own, and the large table potatoes. FARM CULTIVATION 73 Storing. — If a large frost-proof shed or barn is available, and the crop is not a very large one, they can be stored under cover. The usual practice, how- ever, is to store them in pits or clamps. The pits should be placed in a dry, well-drained position and as near the gate of the paddock as possible so as to avoid any carting over loose, wet soil during the winter. The site for the pits should be levelled, and a little soil thrown round the margins to mark them off. The tubers are piled up in a pointed heap and then given a covering of clean, straight straw which can be held in position with a few spadefuls of soil. Finally, a layer of soil is added to a depth sufficient to keep out frost and wet. The soil is dug out round the pit, and the straw covered to a depth of six inches, the outside being beaten with the back of the spade to form a smooth surface which will throw off heavy rain. In very frosty districts it will be necessary to thatch the pit on top of the soil with straight straw which will be held in position with spadefuls of soil. To prevent newly dug tubers from heating, ventil- ators are provided on the ridges of the pits by placing drain pipes or wisps of twisted straw at intervals of six feet. When digging the whole crop, big, medium, and little are sometimes stored away together, and later on when growers have more time the work of grading is carried out, either by riddling or hand picking. In every case scrupulous care has to be taken to pick out all damaged or diseased tubers before they are bagged up for market. Carefully graded clean tubers always command a much higher price than an uneven lot with a liberal sample of the soil in which they were grown included in the sacks. 74 POTATO GROWING FORCING THE POTATO. Though the old tubers can be kept until the new crop is ready to dig in December or January, they become so unsatisfactory and there is such a lot of waste in preparing them, that there is always a keen demand for the new tubers at very satisfactory prices to the grower. In the Auckland district it is quite easy to have potatoes ready to dig in the months of November and December, and they are sent all over the Dominion where they meet with a ready sale. New potatoes deteriorate so quickly when dug, that when they are sent to a distant market they can never compete with the home grown article, either in flavour or appearance. There are favoured spots in the South Island and the southern end of the North Island where potatoes can be dug in November, and the fortunate possessors of these patches usually reap a rich harvest. Potatoes can be forced quite readily either by planting them in pots and boxes which are placed in a greenhouse, tomato house, or vinery, or they can be planted in hot or cold frames. The selection and treatment of seed has already been fully described, but it will be well to note here that cut seed should never be used for forcing. It is the greatest bulk that can be produced in a limited space in the shortest possible time which pays, not the heaviest crop from a given quantity of seed. To save time when forcing potatoes for a very early crop, the boxes of sets should be placed in a heated greenhouse or vinery. At the time of planting, the shoots should be not less than three-quarters of an inch in length, and stout, green, and plump, so that they will grow rapidly when planted in the soil. Not more than three FORCING 75 shoots should be left on each seed. Though sturdy sprouts are not easily broken off when handled, every care should be taken not to damage them when planting. As most of the early varieties make short shaws they may be considered as dwarf, and they develop both their foliage and their tubers quickly. Conse- quently, the crop per plant is never a heavy one. It is therefore necessary to have the soil in which they are grown as rich as possible and the plant food in the most readily available and easily absorbed form. The soil to be used should consist of good turfy loam or bush soil two parts, leaf-mould one part, well rotted manure one part, and sharp sand half a part, with a six-inch potful of superphosphate and wood ashes to every barrowload of the mixture. The soil should be prepared some time before it is required, and kept in readiness either in a dry shed or in a heap covered with sheets of iron. To destroy insect pests should they appear in the soil, a six-inch potful of apterite should be mixed with every barrowload and the heap should be covered with sacks or canvas for a few days to keep in the fumes until the insects are killed. In a small way, potatoes can be forced in pots or boxes or tins. Some rough materials are placed in the bottom to provide good drainage, then the pot or box is filled half full with the prepared soil, and finally the tuber is set in the middle and covered up to within an inch of the top with the soil. Watering will cause the soil to settle, and later on when the shaws are about six inches high a top-dressing can be given to which has been added a little nitrate of soda or sulphate of ammonia. 76 POTATO GROWING The pots, etc., can be stood on a greenhouse bench, or on the bed among young tomatoes. The plants should be watered carefully until the shaws reach their full development, when they should be given as much light as possible to encourage the formation of tubers. Potatoes can also be forced in frames which are placed over a gentle hotbed, or in those heated by hot-water pipes. To make a hotbed, a heap of fresh stable manure with plenty of straw in it and a heap of leaves should be thrown up in a loose heap in the proportion of two parts manure to one of leaves. Fermentation soon commences and the heap has to be turned, the outside of the first heap being placed on the inside of the second one, to secure complete fermentation throughout. The manure has next to be built up into a square heap adding it in thin layers and tramping it firmly as the building proceeds. It should be deep enough to maintain a gentle heat for about two months, and should extend for two feet beyond the sides of the frame all round. The frame is now set on the heap and six inches of the prepared soil placed inside it. "When the temperature has subsided to from 70° to 80° Pah., the seeds may be planted in rows fifteen inches apart with nine inches between the sets in the rows. The frame should be deep enough to allow a foot of space between the top of the soil and the glass, and when the soil settles another three inches of soil should be added to take the place of the earthing-up. On cold nights the frames should be covered with bags or mats to keep out frost and prevent the temperature from falling too low. On all favour- able occasions the sashes should be tilted up at the top to admit fresh air, but care has to be taken to NEW POTATOES PEOM OLD ONES 77 avoid cold draughts which would seriously check the growth. Very little watering will be required as there is little evaporation during early spring, but the soil should on no account be allowed to become dry. As the days lengthen and the sun heat increases, more ventilation can be given and likewise more watering will be required, when fine weather should be chosen so that the lights may be removed. If all goes well the crop should be ready to lift in from eight to ten weeks from the time of planting, but much depends on the outside temperature and the amount of sun- shine. Potatoes can also be grown in cold frames, when they will come in later than those grown in heat but earlier than those planted outside. The frames should be from eighteen inches to two feet deep at the lowest end, and they should be placed in a warm, sheltered position where they are fully exposed to the sun. The cultivation is similar to that described above for hotbed forcing, except that more room must be allowed. Any of the early varieties are suitable for forcing, such as Ashleaf Kidney, Sharp's Victor, Early Puritan, Sutton's May Queen, Midlothian Early, and Myatt's Ashleaf. NEW POTATOES FEOM OLD ONES. This is a novel method of potato growing, described by a gardener in England in one of the gardening periodicals. The system is, however, a very old one, having been practised by a bygone generation of gardeners. At one time it was considered that the variety Windsor Castle was the only one which was suitable, but it is now known that practically any good keeper will give satisfactory results if treated intelligently. 78 POTATO GROWING When it is intended to practise this method of potato growing systematically, the tubers should be selected at the time of digging, and as the new tubers are produced directly from the old ones it follows that they should be of fairly large size, the bigger the better. As it is necessary to retard the growth the first season as much as possible, the tubers should be stored away in a cool, but not too damp, cellar or cave where the temperature will not exceed 50° Fah. and will not fall to within a few degrees of freezing point. As growths push at the usual growing season they are rubbed off until the following autumn, when growth usually ceases. During the winter the tubers which have been specially prepared can be placed in frames on a gentle hotbed and covered with just sufficient soil to prevent the young tubers, which grow directly out of the old ones, from being exposed to the light and becoming green. When the new tubers form they are removed and the old ones put back to pro- duce a second crop which, strange to say, they will do after a short interval, and it is curious that even in frames very little root action takes place and practically no leaves appear. Where a dark cellar or cave is available or a mushroom house can be used the old tubers are simply laid out on shelves or benches in a single layer, these being covered with a few inches of old potting soil to prevent them from shrivelling too much. When space is limited and a heated greenhouse or vinery available, the tubers which have been pre- pared can be placed six inches apart in a fairly deep box, a layer of soil three inches deep is placed on top of them and another layer of tubers added and A potato digger at work. See pages 72 and 88. VARIETIES 79 this is continued until the box is full. When the final layer of tubers is added the box can be placed in the greenhouse where a temperature of 60° F. can be maintained. The young tubers soon begin to develop, and they continue to provide new tubers of good size and quality from autumn right on through the winter. By some they are considered to be disappointing as to flavour, but others consider they are quite as good as those forced in frames in the usual way, and they are certainly less trouble. It is advisable to use a main crop variety, such as Windsor Castle or Arran Chief, and though it would not be desirable to adopt this method when potatoes are scarce and dear, it would be a useful method of using some of the old tubers when there is a surplus at the end of the season. It would appeal most to those people who desire to have new potatoes all the year round. VARIETIES. Many of the old varieties which were much esteemed by growers thirty or forty years ago have now almost entirely disappeared from cultivation. This is largely owing to the careless and faulty methods adopted for seed saving and selection, which has so weakened their constitution that they fail to produce a paying crop and they become extremely susceptible to the attacks of disease. Any plant which is propagated in a vegetative manner by means of cuttings or tubers has a tendency to deteriorate unless the greatest care is taken in selecting the cuttings or the seed tubers. These old weak varieties, so very susceptible to disease, are in time displaced by newer and more vigorous varieties, and though it is doubtful if many of the new ones are as good as the old ones when 80 POTATO GROWING they were strong and healthy, they are more vigorous and disease-resisting than the older run-out sorts. Quite a number of the newer varieties which are introduced from time to time with a great flourish of trumpets and much advertising fail to make good. Either they do not suit the soil or the climatic con- ditions, or they fail to satisfy the desires or expec- tations of the purchaser either in shape, flavour, cropping, or cooking qualities. Northern Star, Eldorado, and Epicure are varieties which enjoyed popularity for only a short time. Though there are quite a number of varieties with coloured skins these are not so popular as they were at one time, and there is no doubt that it is a desire to obtain a worthy successor to the old and at one time much esteemed Derwent which causes growers to persevere with them and to try all new varieties. In the following lists the varieties have been divided into First Early, Second Early, and Main Crop kinds, and though many of the old ones that are seldom seen have been included there are also some of the newer ones which are highly spoken of in Britain but which are probably not yet procurable in New Zealand markets. Firit Early. Dunotter Castle (Sutton). — This variety, intro- duced in 1915, possesses all the essential qualities of a high class early potato. It is an abundant cropper, free from disease, flesh white, and when cooked, of splendid appearance and flavour. It is kidney shaped, flowers lilac, shaws dwarf and compact. Al (Sutton). — A heavy cropping first early round potato, equally adapted for forcing and for early digging in the open. A good cooker, with dwarf, dark green, erect foliage. VARIETIES 81 Ninety-fold (Sutton). — White kidney potato, heavy cropper and excellent cooker. Foliage erect and dwarf, tubers nearly all large size. Harbinger (Sutton). — A great favourite in the colder districts where it produces extraordinary crops. Tubers elongated with shallow eyes, good cooker, ripens early, and suitable for the earliest crop and for exhibition. Flowers white. Snowdrop. — White kidney, skin clear, flesh white, and mealy when cooked. Abundant cropper, flowers white. Early Rose. — Very early pink-skinned variety, cooks well and is an average cropper. Early Puritan (of American origin). — A round variety which ripens early, a good cooker and heavy cropper. Robin Adair. — Kidney shaped, pink-skinned potato, very early, good cropper, and seems to be suitable for moist, peaty soils. Sharp's Express. — One of the best croppers of all the early kinds, white flesh, handsome appearance, matures early and is a good keeper. May Queen (Sutton). White kidney potato with dwarf shaws, flesh white, very good flavour when freshly dug. Fine for forcing and early outdoor cultivation. Midlothian Early. — White kidney potato, good cropper, strong grower, and good cooker. Jersey Bennes. — One of the best and earliest potatoes in the Dominion. It is not only a good first early but if allowed to mature will keep as long as any variety. Produces a heavy crop of perfectly formed tubers, clean skinned, with shallow eyes. Both skin and flesh white, and quality excellent. Ashleaf Kidney. — An old favourite and still worth growing when a good strain of seed can be obtained. Very early but not a heavy cropper. 82 POTATO GROWING Colonist (Webb's).— White kidney. Tubers smooth with shallow eyes, very heavy cropper, cooks white and mealy, disease resisting, good garden and exhi- bition variety. Arran Eose. — Oval with white flesh. This is a new Scotch variety, a great improvement on the old Early Eose, being very shallow in the eyes, a nice size tuber, and of good cooking quality. Sir John Llewellyn. — Oval, white flesh. A Welsh variety, said to be earlier than Ash Leaf Kidney, grows fairly tall, tubers white, with shallow eyes. Though Epicure is classed as a second early by some growers it is the variety which is most largely grown for the early market on the Ayrshire coast, and it would be found an excellent kind for windy situations in New Zealand. Second Early. Second earlies take a little longer to mature their tubers than the first earlies, and consequently pro- duce a heavier crop. They keep quite well, and can be grown as main crop should they not be required for digging green. Supreme (Sutton's). — Pebble shaped, white skinned, smooth tubers with shallow eyes. A splendid cooker and heavy cropper, but should be planted in a warm sheltered position. Windsor Castle. — White oval shaped tubers, heavy cropper and excellent cooker. Good flavour and a good market garden variety. British Queen. — Has white oval shaped tubers, good quality, and suitable for either garden or field cultivation. Duchess of Cornwall. — White, round, large, hand- some tubers, shape somewhat flattened. Shaws dwarf and robust. Good cooker, heavy cropper, and a good exhibition variety. VARIETIES 83 Epicure Sutton. — A heavy cropper, with strong robust shaws which stand the wind well. Flesh white, good flavour, and a favourite with market gardeners and farmers. Ideal (Sutton). — Tubers kidney shaped, attractive, with smooth skin and shallow eyes. Shaws distinct, flowers white. Beading Russet. — "Was awarded first prize at the National Potato Show as the best round potato. Red russeted skin, shape flattish round, flesh lemon white of excellent quality. Though a second early the tubers keep well. Seedling (Sutton). — White pebble shaped tubers. Large, with shallow eyes and russety skin, cooks well, and crops freely. Arran Comrade. — Round flat shape with white flesh. This is a new variety which bids fair to become very popular. It produces a heavy crop of medium sized tubers, having very shallow eyes and a white skin. Royalty Carter. — Oval, white flesh. This grand variety was awarded the silver medal for the best white potato at the National Potato Show. It is a medium grower, and very productive on all soils, the tubers being white, dry, and of fine flavour when cooked. Main Crop Varieties. These take longer to mature than the earlies and second earlies, and consequently produce heavier crops. Their great advantages are that they keep well and are not so liable to start into growth in early spring. White City (Sutton). — This is said to be a great improvement on Up-to-date, and is free from disease. The tubers are ideal kidney shape, of the finest exhi- 84 POTATO GROWING bition type, with very few eyes, and when cooked are dry and floury. Dark green foliage with lilac flowers. Up-to-date. — Probably the favourite main crop variety in the South, and when a good strain of seed is obtained it is hard to beat, either as a heavy cropper, or for its flavour and quality. It is also a favourite with exhibitors. Arran Chief. — An excellent potato, tubers round with a russety skin, eyes not deep, cooks dry and floury, and is an excellent keeper. Produces very heavy crops, and as the shaws grow strongly on rich, well manured ground it should be planted further apart than any other variety. Dalmeny Beauty. — White kidney. Tubers with shallow eyes and netted skin, very heavy cropper and good cooker. A reliable field potato. Colonist (Pindlay's). — Coloured round. Tubers pink coloured, an enormous cropper, first-rate cooker, and disease resisting. Discovery (Sutton). — "White round. Tubers large pebble shaped, with russety skin, very heavy cropper, and cooks dry and floury. Flowers white. Eldorado. — White oval. Greatly praised at one time, and created a sensation in 1904 when it realised fabulous prices. Flowers heliotrope tipped with white. Magnum Bonum (Sutton). — Tubers good shape with shallow eyes. At one time one of the most popular varieties in Britain both for garden and field cultivation. Good cropper. King Edward VII. — Coloured kidney. Tubers of a handsome shape, eyes tinged with pink, very heavy cropper, an excellent cooker, disease resisting, good for garden cultivation and for exhibition. Langworthy . — White kidney, heavy cropper, excellent cooker. VARIETIES 85 Some of the newer varieties which have proved themselves in Britain but are not in commerce in the Dominion yet, but are sure to be available soon: — Great Scot. — A white round potato, heavy cropper, and good flavour. A second early variety, but also good as a main crop. Majestic Maincrop. — Tubers white, of rather long and slightly flattened kidney shape, with very shallow eyes, and a smooth, clear, white skin. It is said to be the best variety introduced since Up-to-date. Its quality is first rate in every respect, while its cropping powers are enormous. Majestic was raised by Mr. Findlay, the celebrated raiser of Up-to-date and British Queen. A trial plot cultivated by a lady produced a crop at the rate of 194 tons per acre. Kerr's Pink. — Maincrop. Tubers round to oval, very handsome in shape and the most delicately tinted pink. Flesh white, flavour and cooking qualities excellent, yields a very heavy crop of good sized tubers. This variety was awarded a gold medal, and is considered one of the best main crop varieties in commerce. As this is a strong grower like Arran Chief the rows require to be three feet apart. On a trial plot it yielded 16 tons to the acre. Arran Victory. — Round, white flesh. A coloured variety with purple skin; strong grower and good cropper. Golden Wonder. — A white-fleshed kidney of excep- tionally good cooking quality, and a splendid keeper. Tinwald Perfection. — Kidney, white flesh. This variety produces a fine crop of nice shaped shallow- eyed kidney potatoes, and is a splendid keeper. 86 POTATO GROWING TOOLS, IMPLEMENTS, AND MACHINES. Besides the ordinary farm implements used in the cultivation of the soil, there are quite a number of labour-saving machines whieh have been invented during recent years to simplify and expedite the planting, digging, and sorting of the crop. When ploughing it is necessary to go deeper than an ordinary furrow, and it is now possible that an improved tractor will be introduced which will be able to turn over the top furrow and stir up the subsoil to a depth of about six inches in one act. Disc harrows, tine harrows, and a good strong culti- vator are necessary for breaking up newly ploughed grass land and bringing the soil into a good state of cultivation previous to planting, and if the soil is lumpy a Cambridge roller should be employed to crush the clods. When planters and diggers are used it is most important that the soil be well cultivated and all the sods or clods cut or broken up; but even when these implements are not used all subsequent oper- ations are much easier to perform when the soil is in good condition. Planters. — For planting many farmers use an ordinary single mould-board plough, but the work is far better done when a double mould-board plough is used. This can be regulated according to the width of the drills and the depth of planting, and it has an attachment for marking off the next drill, thereby ensuring straight and even planting. The double mould-board plough is also very useful for earthing up the crop and is certainly much easier to work than the attachment for the purpose which fits on to the Planet Jr. cultivator. There are several cultivators on the market, but the Planet Jr. one-horse cultivator is probably as N.Z. Pipt.o/ l„i k: Irish blight on leaves of potato. See page 9J. Potato moth. See page 103, A Y.S. W . Dept. of Agriculture. IMPLEMENTS, ETC. 87 suitable as any for working between the ridges." It is light and easily reduced in width to suit the distances between the drills. For working the ridges after planting there is a very useful implement called saddle harrows used in Scotland. It is like the leaf of an ordinary harrow bent over like a saddle, it fits over the ridges and the tines work both the top and the sides destroying many of the seedling weeds which are apt to appear before the potatoes come through the ground and shaking out any sods which may have been turned up during the drilling and covering. One horse can draw two sections harrowing two ridges at a time, and there is a handle attached to each to enable the driver to guide them. Many planting devices have been tried, and there is a simple one suitable for small plots, manufactured in Lincoln, England. This implement consists of three metal tubes which are brought together at the top but spread out fanwise at the bottom so that three sets are planted at one time. The distance between the tubes can be regulated, and it is breast high so that the stooping which is so severe on the back is obviated. As the operator takes a step forward three sets are dropped into position at the correct distance apart in one act. The Iron Age planter is in use in several districts and is considered a valuable labour-saving maehine. It is drawn by two horses and operated by two men, or a man and a boy. It opens up the drill, places the seed in position, and covers it up again all at once. The seeds are shaken out into a pocket by an elevator wheel which in turn drops it through a short spout into a horizontal feed wheel also provided with pockets. The driver watches the horses and guides the machine; the second man watches the planting 88 POTATO GROWING wheel and when he finds that a pocket has no seed he supplies one from a pile within reach, or if a pocket gets two pieces he removes one. These planters are only useful for planting seed of a uniform size, and are of no use whatever for sprouted sets. Sprayers. — As spraying is now a recognised part of good cultivation several machines have been invented for performing the operation rapidly and thoroughly. The Iron Age sprayer, drawn by two horses, can spray from four to six rows at a time. It is operated from the centre, has a perfect working relief valve and a big air chamber, is thoroughly protected against corrosion, and is easily shut off from the seat. It is made in from four to six drill sizes with a 50 or 100 gallon wood or steel tank and a revolving mixer. For small areas an ordinary knapsack sprayer is quite suitable. The operator pumps with one hand and regulates the nozzle with the other. There is another useful sprayer which is filled three parts full with the spraying mixture, air is pumped in and the pressure is sufficient to expel the spray with enough force to form a fine mist. Diggers. — Where the area is not large enough to employ a mechanical digger the double mould-board plough can be used, or a plough with two sets of steel tines which are substituted for the mould-boards can be used. The share passes under the roots raising up the potatoes which are spread on either side fairly free from dirt. A considerable number of the potatoes are buried but these are unearthed by the cultivator or harrows. The Scotch potato digger is simple in construction, strong, of fairly light draught, and easily drawn by two horses. The curved share at the rear of the IMPLEMENTS, ETC. 89 machine passes underneath and loosens up the roots which are caught by the revolving forked tines. These throw out the potatoes and the soil on one side, the potatoes being spread out on the surface, a screen which is hung out at some distance from the side preventing them from being thrown too far. The share can be lowered to any required depth or raised clear of the ground when the machine is being shifted from place to place. This machine is suitable for digging the matured crop but would be apt to bruise and damage immature tubers. There is also a Scotch machine which raises the potatoes with a flat share in front and passes them over steel tines on to the surface behind. The Iron Age digger works in a similar way. It pushes under the roots elevating the potatoes on to the body of the machine which separates them from the soil and deposits them on the surface behind. Potato Sorters. — When removing the potatoes from the pit or clamp they have to be sorted and graded before being sent to the market, and this work is considerably reduced by the many clever devices which have been placed on the market. Probably the most elaborate and perfect is the Wilson Dobbie potato-dressing machine, made by Mr. David Wilson, Eiccarton, Linlithgow, Scotland. In this the potatoes pass down a revolving sieve of hexagonal shape which separates them into three sizes as they pass along. The table and seed sizes drop on to a carrier running at a sufficiently low speed to allow time for picking out all diseased and damaged tubers as they pass along. This machine can be worked by hand and is sufficiently expeditious in dealing with the tubers to keep a man feeding it all the time. 90 POTATO GROWING For sorting small crops the sieve can be fitted on to a frame or stand on which it will work. A simple stand is made from four stout corner posts three feet long and cut out of three by three inch timber, and these are held in position top and bottom by pieces of six by one flooring boards, strips being nailed across three of the sides to keep the frame rigid. Two pieces of hard wood are fixed across the top on which the sieve will rest, and work, and a piece of half-inch wire netting is fixed on to a frame and nailed at an angle inside the frame so that it will allow the dirt to pass through and throw the small potatoes out on one side. The one and a half or one and a quarter inch sieve allows the dirt and small ones to pass through, and all diseased or damaged tubers are picked out as the grading proceeds. A machine that will remove the sprouts which will appear on the old tubers in spring, or some treatment which will prevent sprouting at all, is much needed to reduce the cost of hand picking and sorting out. DISEASES OF THE POTATO. Fungoid Pests. The potato like all other useful cultivated plants is attacked by both insect and fungoid pests, and one of these is so formidable that at one time it threatened to exterminate this useful food plant altogether. Prevention is better than cure, and good soil preparation, a proper system of cultivation and manuring, scientific seed-saving and selection, and the introduction of new and robust varieties all combine to keep the different diseases in check. But DISEASES 91 occasionally when weather and other conditions are unfavourable blights make their appearance, and a description of the methods of combating blights is a necessary part of a book on the potato. Phytophthora Infestans. — The disease sometimes called "Irish Blight" is the most destructive of all the diseases. It appeared in Germany about 1845 and soon spread all through Europe, caused a famine in Ireland, and extended to America. Though this disease is not dreaded to the same extent now as when it first made its appearance, when climatic conditions are suitable for its propagation and distribution it often reduces the crop by half and sometimes destroys most of the tubers. Even in the most favourable seasons a considerable amount of damage is done, and a careful and progressive grower should take measures to reduce this loss to a minimum and adopt spraying as a regular part of good cultivation. Phytophthora infestans is a fungoid disease, and first shows itself in the form of brown spots on the leaves which gradually curl up and shrivel, finally turning black. Under favourable weather conditions both stem and leaves become black and rotten within a few days and emit a very disagreeable smell. If the brown patches are examined with a pocket lens minute white mould-like bodies will be seen on the undersides of the patches more especially towards the margin. When the attack is slight and the foliage is not destroyed at once the conidia are produced in rapid succession and are conveyed to neighbouring plants by rains, winds, animals, etc., and by such means the disease spreads rapidly. The simultaneous outbreak of an epidemic in extending over a wide area is not necessarily due to infection by the conidia, but may be due to the 92 POTATO GKOWING presence of the hybernating mycelia of the fungus in the tubers which were planted for seed. Mr. Massie considers it doubtful if the zoospores which are liberated from the conidia are washed down to the young tubers, and thinks that they are infected direct from the seed. The brown stains in the tubers infected by the disease are too well known to require description. "When the disease is very evident probably no one would use the tubers for seed, but there are instances when the disease does not show on the surface, or it is so slight that it is easily overlooked when the potatoes are planted. The disease is passed from the old infected tubers direct to the young ones in a vegetative manner with- out the formation of spores on the part of the fungus. In this way disease is spread during bright, compara- tively dry seasons, the mycelia not being able to in- vade the above ground portions, and the stem and leaves of the plants with affected tubers being per- fectly clean and healthy. It is by this means that the disease is spread from infected tubers to the sound ones when they are stored in pits or store houses, and it is a well established fact that the disease has spread through what appeared to be sound tubers when they were being conveyed to the market. This fact further emphasises the need for storing seed potatoes under conditions unfavourable for the spread of the disease, and these conditions are as far as possible open air and sunlight. Potato growers all over the Dominion know that if we get a few cloudy, damp, sultry days in January or the beginning of February an epidemic of the disease will spread over an entire paddock, and in some instances an entire district, and in a few days the green stems and leaves are converted into a black DISEASES 93 stinking mass. The mycelia, favoured by the weather conditions already indicated, take possession of the stems and leaves when these are young and succulent. Life History of the Disease. — The hybernating mycelia which attack the tubers forming brown spots are also said to stick round the eyes and even to find shelter in the dirt which is too often found sticking to the seed, and when weather conditions are favour- able they spread up the stems to the leaves. The mycelia attack the young leaves and stems and soon form clusters of conidiophores which emerge through the stomata. These are simply and sparingly branched, and appear like mould when examined with the hand lens. The conidia are produced on the conidiophores, and their contents quickly break up into zoospores which are liberated. When these come into contact with moist potato leaves they quickly germinate, penetrate the tissue and develop mycelia which in turn produce more spores. It is generally considered that the spores are washed down through the soil to the tubers, and deep planting and high ridging are frequently resorted to to prevent any danger of infection from this source. The preventive and remedial measures suggested are as follows: — As the disease is transmitted from the seed to the young tubers it is most important to select seed free from disease and to store it under conditions which are unfavourable to its spreading. Spraying with fungicides. Repeated experiments have demon|strated that it is possible to keep the disease in check and in some cases to prevent infection altogether by spraying with fungicides, such as Bordeaux mixture and the copper soda mixture, to use either of which means an increase of from two 94 POTATO GROWING to four tons per acre over those not sprayed, and in some years it means all the difference between success and failure. Bordeaux mixture is composed of copper sulphate 4 lbs., quicklime 4 lbs., and water 40 gallons. The copper sulphate should be 98% pure, and it should be tied in a coarse sack or a bit of scrim and hung in an earthenware or wooden vessel holding at least 4 gallons, so that it is just covered with water. The lime which should be freshly burnt, should be moistened and allowed to swell and slake slowly. When it has been well slaked it should be worked into the consistency of thick cream, and gradually diluted to four or five gallons. The milk of lime so formed must next be strained through a fine sieve or a piece of sacking to remove all the grit, and it should then be further diluted with water to form about 10 gallons. The copper sulphate solution is put into a Cask and milk of lime gradually added and thoroughly stirred in, followed by the balance of the 40 gallons of water. It is most important that there be no acidity in the mixture, and a good test is to place a clean steel knife blade in it for a minute or two. If copper be deposited on the steel, or if the blade takes on the appearance of copper plate the mixture is unsafe and should not be applied to tender foliage until more lime is added. If, however, the knife blade is unaffected the mixture is safe. Another test is to dip a strip of blue litmus paper into the mixture, and if it turns red add some more lime until the paper remains blue, when it is quite safe. The spraying should be done in fine and dry weather and the mixture applied to both the under and upper sides of the leaves, for it is usually on DISEASES 95 the under sides that disease appears first. If it should rain immediately after spraying, the operation should be repeated as soon as the weather clears up, and if the foliage is wet a stronger mixture can be used. To get the best results it is necessary to spray twice and in some seasons three times, the first spraying be- ing given just after the first earthing-up and the next spraying a month later. About 120 gallons of the mixture is sufficient to spray an acre. It is also important to keep the mixture well stirred throughout the operation of spraying. Copper and Soda Mixture. — This mixture is recom- mended by many. It is easy to prepare and the soda not being so gritty as lime it is easier to apply. It consists of copper sulphate, 98% pure, 8 lbs., washing soda 10 lbs., and 40 gallons water. The copper sulphate can be crushed and placed in canvas bag and suspended in a vessel holding 5 gallons of water, or it can be dissolved in boiling water. The soda is dissolved in another 5 gallons of water and the two solutions mixed together, and kept well stirred. Finally, the remaining 30 gallons of water are stirred in. To make a quantity suitable for a small garden patch use 2 lbs. of sulphate of copper, 1\ lbs. of washing soda, and 10 gallons of water instead of the quantities specified above. To ascertain if the mixture is in the right propor- tions test with the blue litmus paper, if it turns red add more soda, till with further tests it remains blue. As both the Bordeaux and the soda mixtures deteriorate quickly they should be applied within two days after being prepared, and in every case wooden vessels should be used for mixing and holding them. As copper sulphate is poison it should not be put into buckets or casks which are used for holding drinking water. 96 POTATO GROWING Spraying with either Bordeaux or soda mixture has a beneficial effect on the foliage apart altogether from its effect on the disease, the leaves look greener, cleaner, and healthier after spraying, and even when there is no disease to be seen the crop benefits by spraying. Black Scab or Wart Disease (Synchytrium endobioticum) . — This disease is sometimes called the cauliflower, canker fungus, or black scab, and it attacks the tubers and shaws of the potatoes giving rise to irregular outgrowths, which suggest the resem- blance to a piece of cauliflower. In bad cases these warts may appear on the surface of the soil, and can be detected at the base of the shaws as yellowish green masses. "Warts and wrinkles appear at first in the eyes of the young tubers and later on several warts by growing together form a brown, spongy scab which finally rots and becomes black. This disease causes more damage in gardens and allotments where potatoes have to be grown in the same ground year after year than on farms where a definite system of rotation of crops is followed. The spores which are produced in the diseased tubers and shaws are not only capable of infecting healthy potatoes the following year but they appear to be able to remain dormant in the soil for several years. The diseased tubers are the usual source of infec- tion, and the spread of the disease from one holding to another is mainly attributed to the planting of diseased seed. Remedies. — All diseased tubers should be burnt, or if they are not too badly affected they should be boiled before they are fed to stock, and in the case of any apparently healthy tubers which are to be saved for seed from an affected crop they should be DISEASES 97 dusted with sulphur before storing, care being taken that the latter is well dusted into the eyes of the tubers. 4 to 5 lbs. of flowers of sulphur would be sufficient to dust a ton of tubers. It is also equally- advisable to be careful in the use of sacks which have contained diseased tubers, for it is quite possible that the spores of the disease may be present in them. In gardens where a single diseased tuber has been found, in addition to dusting the tubers with sulphur, the sets when placed in the drills should also be dusted with it, and before the potatoes are earthed up the surface soil round the shaws should be sprinkled with sulphur. When no other land is available for the potatoes and they must be grown on the same patch year after year, if this disease appears the soil should be trenched in the autumn and a dressing of gas lime applied at the rate of three pounds to the square yard. Some varieties are more susceptible to attacks of this disease than others and only those which are considered immune should be planted. In England this is a notifiable disease under the Destructive Insects and Pests Acts, 1877 and 1907, and occupiers of land on which the disease occurs must at once report it to the Secretary of Agriculture. Neglect to report renders the owner liable to a penalty not exceeding £10. This wart disease is not to be mistaken for the small wart-like growths on the skins of tubers which are grown in sour land, on land which has been too heavily manured, or where the tubers come into contact with the fresh farmyard manure. Though these warty-looking tubers are unsightly the trouble is only skin deep, and is caused by the tubers trying 98 POTATO GROWING to repair the damage done to the tender skins by the acid in the manure or soil. The remedy for this disease is to drain and culti- vate the land well, to give reasonable applications of lime in the early spring, and to dig in the manure in the autumn or early winter so that it may become thoroughly incorporated with the soil before the planting season. If scabby potatoes have to be used for seed they should be treated with a solution of corrosive sublimate (bichloride of mercury) before planting. Leaf Curl (Macrosporium solawi). — In some seasons and districts the leaves of the potatoes curl and pucker up and then turn yellow. This condition is due to a fungus which is reproduced from hybernat- ing mycelia found in the tubers used for seed, and is spread in a similar way to the Disease or Irish Blight. The attacks of this disease are understood to be due to the weakening of the constitution of some varieties due to the constant propagating in a vegetative manner and the lack of care in selecting and saving the tubers used for seed. The leaves curl and the stem droops before there is any evidence of the cause of the injury. At a later stage, however, the stem and leaves bear numerous blackish olive, minute, velvety patches of various forms and sizes. These patches consist of dense masses of dark coloured conidia, Macro- sporium solani, the cause of the disease. As soon as the leaves begin to curl a microscopic section of the leaves reveals the presence of a dense mass of mycelia, which chokes the moisture-conducting passages, hence the leaves curl and the stem collapses owing to lack of food. INSECT PESTS 99 When the plant is badly affected the mycelia pass from the stem and leaves to the underground branches and the young tubers. If the disease appears early in the season the crop is very much reduced, many roots not producing more than a few very small tubers and some none at all. Spraying with Bordeaux mixture or the soda and copper mixture as recommended for the "Disease or Irish Blight" is the best preventive, and a change of seed or variety is also desirable when this disease appears. INSECT PESTS. Wire-worms. — Potatoes are attacked by insect as well as fungoid pests, but none are so destructive or so widely distributed as the Irish Blight. The most troublesome insect pest is the wire-worm which eats its way into the tubers, in some cases riddling them through and through and rendering them quite useless for human food. It is most unfortunate that this pest should be so bad on newly broken up pasture or grass land, for, as we have seen, potatoes are the most suitable crop to take off new land. The wire-worms which are about an inch to an inch an a half long are brown in colour with a shiny hard skin and six legs. The false wire-worm, the millipede, has many more and is not anything like so destructive. It is the grub stage of the click beetle, a little insect well known to children, who catch them and turn them over on their backs for the pleasure of watching them regain their proper position by giving a spring into the air. As they jump they give a little click, hence the name click beetle. The eggs are laid on the soil near the roots of the grass and other plants or occasionally among the 100 POTATO GROWING lower leaves where they clasp the stem. When the grubs are hatched out they commence to eat, at once devouring the underground stems and continuing in the devouring grub stage for several years. This is the reason why wire-worms are so destructive. Most other insects pass through all their stages in one year, and may be kept in check by keeping the soil bare fallowed and clear of weeds so that they have no shelter for the deposit of their eggs. Wire-worms go deeper into the soil during the winter, and when they reach the end of their grub stage they burrow further into the soil and there change into the beetles which emerge in about a fortnight or three weeks. Kemedies. — Owing to the hard skin and the fact that they are able to remain so long in the grub stage, it is very difficult to exterminate them. One method is to chip or plough the grassy turf to a depth of two or three inches, and to burn it scattering the ashes and burnt soil on the surface and working them in. But this is very undesirable, for it destroys the valuable organic matter which should be available for future crops. However, if the soil is badly infected it would pay to treat it as recommended and to replace the organic matter by liberal dressings of stable manure, compost heap, or seaweed. Summer fallowing has much to recommend it, for by ploughing in the grass deeply and keeping the weeds and grass off the surface there is nothing for the grubs to live upon and they have to migrate to another grass patch in search of fresh food. In the case of fresh attacks it would be better to leave the land without crop for a season, to cultivate it frequently to keep down weeds, and to give a liberal dressing of gas lime which should be spread INSECT PESTS 101 on the surface and worked in. This will kill every- thing, the grubs included, and leave the ground clean for the succeeding crop. Another method, usually practised where they attack plants other than potatoes, is to set traps by cutting a carrot or potato in two, putting a piece of stick in it for a handle and mark, and burying it about two inches under the surface near the plants that are attacked. By pulling it out and examining it every day the worms which have only partly eaten themselves in can be taken out and destroyed. Good cultivation and reasonable manuring particu- larly with potash and nitrates is very effective, the plants are stimulated and soon become sufficiently strong to withstand a mild attack so that the crop is too heavy for the worms to destroy it all. It is said that the worms have a strong objection to white mustard, and by growing a crop as a catch crop on newly broken up ground and ploughing or digging it in, the pests will be driven away before the potatoes are planted. It is no use trying half measures with wire-worms and it is better, when the soil is badly infected, to sacrifice a crop to get rid of the pest altogether. Slugs. — Slugs are often very troublesome during a wet spring and on lumpy soil. They eat out the young shoots when they commence to sprout and on rare occasions they attack the young tubers. To check the inroads of this pest scatter newly slaked lime over the surface of the soil several times in succession, and also water the young plants with lime water. Millipedes or False Wire-worms.— These are often confused with the true wire-worms, although they are quite distinct from the latter. They belong 102 POTATO GROWING to a different family, and their bodies are composed of a number of rings each furnished with one or two legs on each side. Owing to the large number of feet which they have they are usually called millipedes or Thousand Feet. There are three harmful kinds, one about an inch long, slender with an ochreous-coloured body, spotted with crimson ; another about an inch long, of a pitchy or leaden hue, and more or less cylindrical in shape; and a third, short flat kind with a lilac-tinted body. These three are very destructive, and attack the tubers as greedily as the wire-worms. They usually eat holes in them and do considerable damage. The remedies recommended for wire-worms are equally suitable for the millipedes. They are more troublesome on badly drained, sour, weed-infested land, and good clean cultivation with reasonable manuring and occasional liming keeps them in check. Colorado Beetle. — This is an American pest which luckily has not become established in this Dominion. The beetles are about half an inch in length, of a yellow colour, with five longitudinal dark lines on each wing case. The eggs are bright yellow when fresh, and are generally laid on the under surfaces of the leaves in patches containing from ten to fifty each. The young grubs are dark brown with black heads, but their colour becomes lighter as they mature. The eggs hatch in from four to eight days, according to the temperature of the air. The grubs eat the tender young leaves where they were hatched, but soon they migrate to the top of the plant and eat the young leaves which are unfolding. The young reach full growth in about three weeks. During the winter the adult beetles live underground at a depth of from _Y <•', T Ti'-jit oj Jgricalturi A. — Tuber of potato attacked by Irish blight. B. — „ ,, ,, potato scab. See pages 91 and 96. Earthed up ready for spraying. INSECT PESTS 103 four to six inches, and when the ground becomes warm again in spring they emerge and soon seek plants on which they can feed and lay their eggs. The best remedy is to spray their food with a poison spray which will kill them when they eat it. Arsenate of lead is very suitable. It is usually supplied in a white paste which is easily mixed with water at the rate of six or eight pounds to a hundred gallons. Strain to remove all lumps which would choke up the nozzle and spray evenly all over the plants both on the upper and under sides of the leaves. Paris green is also a suitable remedy, and it is mixed with water at the rate of a pound to 100 gallons. There is a danger of this spray burning the foliage, and to avoid this it is well to add the milk from two pounds of slaked lime to every hundred gallons of water used. While spraying with either of these poisons the contents of the spraying machines should be kept well agitated. Potato Beetle or Potato Bug. — This is a destruc- tive insect which lives on potato foliage. Its body is green and its head ochreous. Spraying with Paris green or arsenate of lead as recommended for the Colorado beetle is the best remedy. Potato Moth (Lita solanella). — The perfect insect is a small, narrow, brown and grey moth about half an inch across the expanded wings, and the larva, which is pinkish, is about half an inch long when full grown. This is a very destructive insect in the North, but fortunately less common in the South, and as one of the methods of combating the attacks of this pest is to plant clean seed, it is also one more argument in favour of obtaining southern grown seed. The moths generally appear in two broods. The first to appear are the winter brood, and they lay G 104 POTATO GROWING their eggs on the foliage, usually at the base of the leaves, and the larvae by burrowing down the stalks may destroy the crop. The second brood lay their eggs on the tubers themselves, which are liable to be attacked whether left in the field or stored after being dug. They attack the tubers which are exposed, either through careless earthing up or the cracking of heavy soils during dry weather, and they also get into any small or diseased or greened potatoes that may be left lying about after digging. The eggs are usually deposited on the eyes of the tubers, and when the larvae hatch out they feed upon these eyes and later eat their way under the skin or into the tissues of the tubers, causing them to decay or become brownish black. They usually pupate and winter under the skins of the tubers or in any shaws left lying about. To destroy the first crop of larvae when they hatch out on the foliage, it is sprayed with arsenate of lead. This is done when the moths appear, and they are also trapped by placing lamps over basins of kerosene. To prevent the second brood of moths from reaching the tubers, a good hilling or earthing up should be given so that the tubers will be well covered, and to deprive them of a hiding place for the winter all shaws should be collected and burned, all small and diseased potatoes gathered up and boiled before being fed to animals, and all weeds of the solarium family, such as Nightshade and Apple of Sodom, destroyed. Sacks should be sown up at once, and any sacks that have contained infected tubers should be sterilised. Clean seed should be obtained from districts where this blight is unknown or seldom seen, and a system of rotation of crops adopted so that potatoes are not grown on the same field two years in succession. WATS OP USING POTATOES 105 THIRTY-FOUR WAYS OF USING POTATOES OTHER THAN AS VEGETABLES. The following information, extracted from a British Ministry of Food leaflet published during the Great War, shows how it is possible to make a great variety of appetis- ing dishes cheaply by substituting potatoes for a portion of the flour commonly used. The general use of these recipes during the war period effected a remarkable economy in food supplies, and they may be utilised with advantage at any time when potatoes are cheap and flour is dear. HINTS ON COOKING POTATOES. In the following recipes success largely depends on the treatment of the potatoes before making them up in the mixtures used for the scones, cakes, puddings, etc. When sieved potatoes are required, the potatoes should be scrubbed thoroughly, steamed in their jackets, and when cooked and quite hot they must be beaten through a wire sieve with a small jam jar or basin, one at a time. The potato is then floury and the skin is left behind on the sieve. If a sieve is not to hand, peel the potato quickly and mash with a fork. If allowed to get cold before sieving or mashing, the potato becomes sticky and tends to cling together in a mass and only makes the mixture difficult to work and the dish heavy when cooked. In puddings, buns and cakes the best result is given by beating the mixture thoroughly before cooking it. This is essential. Note 1. — If baking powder is used it must always be added after the mixture is beaten. 2. — Puddings should be allowed to stand for a few minutes in the tins or basins after cooking before being turned out. BREAD, BISCUITS AND CAKES. Potato Bread. 7 lbs. flour, 2J lbs. potatoes, 1 oz. yeast, 1 oz. salt, about 3 pints tepid water. Dry and sift the flour if possible, and mix with the salt. Brush or scrub and wash the potatoes and boil them in their skins, then drain and dry them. Select mealy potatoes in preference to waxy ones, which are to be avoided for bread-making. After peeling the potatoes rub them through a sieve, then mix both flour and potatoes together. 106 WAYS OP USING POTATOES Put the yeast in a. small basin and mix with sufficient lukewarm water to make into a batter consistency. Make a well in the centre of the flour mixture, and pour in the pre- pared yeast. Cover with a cloth, and allow this to stand in a warm place for 15 minutes. When the ' ' sponge ' ' has risen mix in gradually about a quart of tepid or lukewarm water, and work into a smooth dough. Put this back into the mixing bowl, cover it with a floured cloth, and set it to rise in a fairly warm place for about 2 hours or a little longer. Then knead the dough thoroughly, using a little more flour to facilitate the process. Now divide the dough into equal sized loaves, put them on a floured baking sheet or board, or else put the dough into greased tins. Allow the dough to rise again for about 15 minutes, then bake in a well- heated oven for about 45 minutes. Potato Bread Bolls. 1 lb. G.B. flour, 1 oz. fat, 1 lb. mashed potato, 1 full tea- spoonful of baking powder, water, salt. Sift the flour and baking powder together and rub in the fat. Meanwhile cook the potatoes, dry well over the fire, pass through sieve or masher. When cool, mix lightly with the prepared flour, add salt to taste, and mix to a fairly stiff paste with milk and water. Boll out to the required thickness, cut to convenient sized rolls, place them on baking sheet, and bake in hot oven from 10 to 15 minutes according to the thickness of the rolls. Oatmeal Biscuits. 3 ozs. medium oatmeal, 2 ozs. flour, 2 ozs. mashed potato, J oz. dripping, a pinch of salt, i teaspoonful of baking powder, water to mix. Miy the oatmeal and flour together in a basin, add the baking powder and the salt and rub in the fat. Next add the potatoes and mix well. Add sufficient water, about a gill, and work to a fairly firm paste. Turn out on to a floured board, roll out J in. thick. Cut into round or square biscuit shapes, place them on a greased baking tin, and bake in a moderate oven from 15 to 20 minutes. Breakfast Scones. i lb. flour, i lb. mashed potatoes, sieved and dried, weighed after cooking, a pinch of salt, 1 oz. dripping, 1 heaped-up teaspoonful baking powder, i gill skim milk or buttermilk. Put the flour into a mixing basin, add the salt, and rub in lightly the fat, then mix with it the potatoes, and lastly add the baking powder. Stir in gradually the milk, and work the mixture to a fairly soft dough. Boll it out on a floured WATS OP USING POTATOES 107 board about 1 in. thick, stamp out by means of a cutter into rounds or ovals, place them on a baking sheet, and bake in a fairly hot oven for about 12 minutes, or else cook them on a hot plate or griddle on top of the stove. These seones can be served cold, but are nicest if served hot. Potato Buns. Boil 4 large floury potatoes, mash and sieve them, add J lb. of flour, a pinch of salt, a teaspoonful of baking powder, and i oz. of castor sugar. Make into a smooth dough with about i gill of milk, and, if liked, stir in about 1 oz. of cleaned currants or sultanas. Form into small bun shapes, and bake in a greased tin for about 20 minutes. Carraway Buns. 4 ozs. potatoes, 1 oz. flour, 4 ozs. ground rice, li ozs. fat, a little chopped lemon or orange rind, and a few carraway seeds, J teaspoonful treacle, J egg (dried egg), J teaspoonful baking powder. Mix the flour and rice and rub in the fat. Add the potatoes, fruit, carraway seeds, egg, and treacle. Beat thoroughly. Lastly, add the baking powder. Stir all well. Form into round buns, place them on a greased baking tin, and bake in a hot oven from 15 to 20 minutes. Potato Bock Cakes. 4 ozs. potatoes (washed, cooked, and sieved), 4 ozs. flour, li ozs. fat, 1 oz. sugar, 1 oz. fruit (currants and sultanas or currants and mixed peel or dates chopped),, J egg, a little grated lemon rind or vanilla essence, 1 teaspoonful baking powder. Bub the fat into the flour, add the potatoes, sugar, fruit, and flavouring. Mix all well, then add the egg and beat all thoroughly. Lastly, add the baking powder and stir well. Put the mixture in dessertspoonsful on a slightly floured baking sheet, and bake in a fairly hot oven from 15 to 20 minutes, according to size. Chocolate Potato Biscuits. 4 ozs. potatoes (washed, cooked, peeled, and sieved), 1 oz. flour, 4 ozs. ground rice, J teaspoonful cocoa, li ozs. fat, i egg (dried egg can be used), a little vanilla essence, 1 table- spoOnful treacle, i teaspoonful baking powder. Mix the flour and gTound rice and rub in the fat. Add the potatoes and cocoa and stir the dry ingredients together; then put in the i egg and treacle and flavouring and beat thoroughly. Finally, add the baking powder and mix well. Turn the mixture on to a floured board, roll out i in., and cut into rounds and bake in a hot oven from 15 to 20 minutes. 108 WAYS OF USING POTATOES MEAT AND POTATO DISHES. Cornish Cutlets. (Sufficient for 5 people.) {£ lb of cold mutton, J lb. of mashed potatoes, 1 yolk of egg, salt and pepper, lemon rind and juice or vinegar, a pinch of grated nutmeg, biscuit meal or pea flour, fat for shallow frying. Cut the meat into rather thick slices of even size if pos- sible. Trim each slice to give it a heart-shaped appearance, or better still, a cutlet shape. Season with pepper and salt and sprinkle over a few drops of lemon juice or vinegar. Mix the mashed potatoes with the yolk of an egg, salt and a pinch of grated nutmeg, also about a teaspoonful of finely chopped lemon rind. Cover each slice of meat completely with potato, shape them again neatly, and smooth over with a knife. Brush over with beaten egg or milk, dip in fine breadcrumbs, pea flour, or oatmeal. When set coat each a second time. Fry the cutlets in hot fat to a golden brown colour, drain on a cloth or paper. Dish up, and garnish with parsley. Serve hot or cold. Potato Dumplings. 8 large potatoes, 3 ozs. flour, 1 oz. cooking fat, 1 egg, 1 teaspoonful of baking powder, salt, pepper and nutmeg. Wash, peel, and boil the potatoes, drain them and rub them through a sieve. When cold add to the pulp the flour and the fat or dripping (melted). Mix well and beat in the egg, season with salt, pepper and nutmeg, and lastly add the baking powder. Shape the mixture into small balls of even size. Cook them in well-seasoned boiling stock or water for about 20 minutes. When done take them up with a slice and drain carefully. Dish up, pour over a rich brown sauce or gravy, and serve hot. Potato Rolls. 6 ozs. cold meat (any kind), 2 ozs. cooked vegetables, rice or other cereal, 1 oz. flour, 1 teaspoonful of chopped onion, a little mixed herbs, seasoning. Mince or chop the meat and the cooked vegetables or rice and herbs, pepper and salt. Add enough stock to form into a stiff paste. Divide into six even pieces and roll into shapes. Potato Pasty. i lb. mashed potatoes, J lb. flour, 3 ozs fat, \ teaspoonful baking powder, a little milk and water. Eub the fat into the flour, add the potatoes, salt and baking powder. Mix to a stiff paste with milk and water. Boll out the paste to about i in. in thickness on a floured WATS OF USING POTATOES 109 board, cut into squares, place a roll of meat on one side of each square, turn over the other side, mark on the top, place on a baking tin and bake for 20 minutes in a fairly not oven. Savoury Batter Pudding. $ lb. of cold meat, i lb. of mashed potatoes, 1 egg, 1 onion peeled and chopped finely, 1 oz. fat, 1 teaspoonful chopped parsley or a little minced herbs, i pint of vegetable stock or milk and water, salt and pepper. Pry the onion in half an oz. of the fat, add the meat which has been previously minced or cut up small. Mix and put away to cool. Put into a bowl the potatoes, make a well in the centre, stir in the egg, then add stock, mix together gradually until smooth, then add meat and herbs, pepper and salt. Put the rest of the fat into a pie dish or baking tin, make quite hot and pour in the batter, bake for 25 to 30 minutes in a fairly hot oven. Savoury Meat Pudding. J lb. cold meat (free from all bone and gristle), 1 lb. of mashed potatoes, 2 tablespoonsful of tomato or brown sauce, 1 tomato, 1 onion peeled and chopped finely, J gill stock or gravy, a little chopped parsley or mixed herbs, pepper and salt. Chop or mince the meat, put it into a basin, add the potatoes, herbs, sauce and the tomatoes (cut up), season with pepper and salt, and nutmeg if liked. Mix well together, and add enough stock or gravy to make a rather stiff paste. Bake in a pie dish or mould that has been greased and dusted with biscuit meal. Bake in a moderate oven about half an hour, turn out and garnish with sprigs of parsley. Meat and Potato Casserole. 1J lbs. mashed potato, i oz. fat, 1 dried egg (for lining of casserole), 12 ozs. cold minced meat, i pint brown sauce, filling. Mix together the mashed potato, egg and fat, season with salt and pepper to taste, then make a border or wall with it in the casserole. Blend the minced meat and brown sauce together, and put into the centre. Mark the potato nicely round the edge. Bake in a moderate oven for 30 to 40 minutes. Send to table in the casserole. 110 WAYS OF USING POTATOES SAVOURY OR CHEESE DISHES. Potato Triangles. 1 lb. potatoes, boiled, steamed, or baked. 6 ozs. flour, 1 teaspoonful salt, 1 teaspoonful baking powder, 1$ ozs. cooking fat, 1 gill of water, J fresh egg (or dried egg). Rub the potatoes through a fine sieve, and mix with the flour, the salt, baking powder, and the fat. Beat up the egg with the water, add this and work the mixture into a fairly firm dough. Roll it out on a floured board about i in. thick. Cut the paste into triangular-shaped pieces of equal size, place them on a greased baking sheet, and bake in a fairly hot oven for about 20 minutes. When baked, slit each open, insert a small piece of butter or a little grated cheese, bacon fat, or dripping, place together again, and dish up. Serve hot for breakfast, lunch, or supper. Potato Finger Fritters. 1 lb. mashed potatoes, 3 ozs. flour, 1 egg, salt, pepper, and nutmeg, fat for frying, parsley. Work in the flour and the egg, well beaten, to the mashed potatoes whilst hot, then season with salt, pepper and nut- meg. Shape the mixture on a floured board into fingers, each about 3 ins. long. Drop them into hot fat and fry to a golden brown. Drain well and dish up. Garnish with sprigs of parsley and serve hot. Potato Aigrettes. These are made from grated raw potato, and form a good breakfast dish. Take 1 lb. grated potatoes, mit them with 1J gills of milk and water, a beaten egg, and 1 oz. grated cheese. Season with salt and pepper, and mix well, add 4 ozs. flour to them and work into a smooth paste. Last of all add a heaped up teaspoonful of baking powder. Drop the mixture from a tablespoon into hot fat and fry to a light golden brown. Drain the fritters, dish them up neatly, and serve quickly. Curried Potatoes and Haricot Beans. (For 5 persons.) 1 lb. cold boiled potatoes, 1 oz. dripping, 1 onion, i pint cooked haricot beans, 1 to 1J gills, stock or gravy, salt, a grate of nutmeg, J oz. curry powder, a squeeze of lemon juice. Cut up into cubes or dice the potatoes, peel and slice the onion, and fry it in a shallow pan in the melted fat. Add the potatoes and haricot beans, toss them in the fat, season with salt and nutmeg, and sprinkle over the curry powder. WATS OF USING POTATOES 111 Moisten with the gravy and lemon juice. Shake the pan well over the fire and let the contents stew gently for about 15 minutes. Serve on a hot diBh. Potato Stew. 1 oz. onion cut in dice, 1 lb. potatoes cut in quarters unpeeled, 1 slice of bacon cut up (set aside the rind for stock), i oz. flour, % pint water or stock, salt, pepper, spice. Fry the bacon, then the onion, add the flour. When brown, add the stock, boil up, put in the potatoes and cook until tender. Dish and serve with chopped parsley. Note. — Slices of cold meat or bully beef, placed on a hot dish, and with the above hot stew poured over it, make a nice hot dish. Potato Butter. Take equal quantities of butter or margarine and cooked, sieved, floury potatoes. Cream the butter in a basin with a wooden spoon, then add the steamed potato, after it has been lightly knocked through a wire sieve. Beat very well, add a little salt, and put aside to set, and use for pastry or table use. Potato Drop Scones. 2 ozs. cooked and sieved potatoes, 2 ozs. flour, \ teaspoon- ful of cream of tartar, J teaspoonful bicarbonate of soda, a pinch of salt, 14 gills milk and water. Sieve the flour into a basin, add the salt, cream of tartar, and carbonate of soda. Mix in the potato and stir in very gradually the liquid. Beat well, then put a tablespoonful of liquid on to a hot griddle or frying pan. Turn carefully as one side browns, cook for about 5 minutes, then serve hot for tea, either plain or buttered. Potato Croutons for Soup. Cut up some large peeled potatoes into thin slices of even thickness, then cut them crossways to form little dice or cubes the same size as croutons of bread whieh are generally served with purees, etc. These cubes are next rolled in pea flour or biscuit meal, and then fried in very hot fat. When of a light brown colour, drain them carefully. Potatoes pre- pared in this way are often used in Prance to take the place of bread croutons. 112 WATS OP USING POTATOES SWEET PUDDINGS, ETC. Sweet Potato Beignets. Wash and scrub about 6 large potatoes, steam them for about half an hour, then peel them and let cool. Next cut each into fairly thick slices, stamp out each slice by means of a round paste cutter, and with » still smaller similar cutter remove the centre so as to get a ring shape like apple fritter. Place the prepared rings on a dish, sprinkle over with castor sugar, and the finely grated or chopped rind of half a lemon, squeeze over the juice of i a lemon also, and allow to stand covered for about an hour. Have ready some rather thin frying batter or pancake batter, dip each potato ring in this so as to cover it com- pletely. Drop these, a few at a time, into hot fat, and fry to a golden colour. Drain well, and arrange the fritters on a hot dish. Dredge over with fine sugar, mixed, if liked, with a little ground cinnamon. Potato Pancakes. 3 ozs. flour, 2 ozs. potato purge made from floury potatoes, a pinch of salt, 1 egg, i pint skim milk or milk and water, fat for frying, sugar to taste. Put into a basin the flour and potato puree, add the salt, and mix thoroughly. Make a well in the centre, put in the egg and a little of the milk, then stir with a wooden spoon, and add gradually the remainder of the milk, beating all the time. See that the batter is quite smooth, and allow it to stand for about an hour. Melt a little fat in a pancake or omelet pan. When hot pour in enough batter to just cover the bottom of the pan, then fry over the fire for a minute or two. Turn over the pancake and fry the other side to a nice golden colour. Proceed thus until the batter is used up. Boll up each pancake and arrange on a hot dish, sprinkle over with castor sugar, and serve hot. This batter can also be used for Yorkshire pudding, Toad-in-the-hole, etc. Golden Pudding. 4 ozs. flour, 4 ozs. mashed potato, 1* ozs. suet or dripping, a pinch of salt, 1 to 1J gills milk and water, 3 ozs. syrup or treacle, J teaspoonful of carbonate of soda. Sieve the flour into a basin, add the salt and baking powder, and mix; next put in the finely chopped suet or the dripping, and the potatoes. Mix the soda with the milk, then add the syrup, stir this into the mixture, and stir all well together. Fill with it a greased pudding basin, cover WAYS OF USING POTATOES 113 it with a greased paper, and steam for about 2 hours. Turn out on to a hot dish, and serve with a little syrup, heated up with an equal quantity of water and a little lemon juice to flavour. Potato Cheesecakes. J lb. mashed potatoes, \ oz. sugar, 1 oz. cooking fat, 1 oz. chopped prunes or dates, J oz. mixed peel, chopped finely, 1 egg, flavouring. Mix the potatoes with the sugar, fat (melted), the pre- pared fruit and peel, next stir in the egg (well beaten), and lastly add a few drops of vanilla or other flavouring essence. Line some greased patty pans with potato short- crust paste, and put a large spoonful of the mixture in each. Bake in a fairly quick oven for about 20 minutes. Potato Short Crust Paste. J lb. mashed potato, \ lb. barley flour, J lb. household flour, 1 level teaspoonful baking powder, a pinch of salt, \ lb. fat, a little water to mix. Prepare the paste the usual way, then roll it out and use as directed. Potato and Fruit Pudding. , i lb. mashed potatoes, J lb. cooking apples, finely chopped, 2 ozs. sugar, grated rind of half a lemon, 2 eggs, potato i lb., shortcrust paste for lining. Put all the ingredients, except the paste, into a mixing basin and stir thoroughly. Place the mixture into a greased pie dish, which has been previously edged with a thin layer of potato shortcrust paste. Bake it in a moderate oven for about three-quarters of an hour. Serve hot. Note. — Any other kind of fruit may be used in place of apples. Treacle Potato Pudding. 1 lb. mashed potatoes, 1 egg, I oz. sugar, 1 oz. ground rice, 1 oz. cooking fat, flavouring essence or other flavouring, 3 tablespoonfuls treacle, i teaspoonful baking powder. Coat a plain charlotte mould whilst warm with a layer ef thick treacle. Mix the potato, egg, sugar and melted butter together, and add a few drops of flavouring essence. Stir in, lastly, the baking powder. Put the mixture into the prepared tin, and cover with a greased paper. Steam the pudding slowly in a pan containing boiling water in a moderate oven, or in a steamer, for about 1J hours. When cooked, turn out carefully on to a hot dish and serve. 114 WAYS OP USING POTATOES Congregation Pudding. 8 ozs. potato purSe, 2 ozs. ground rice, 1J ozs. fat (chopped suet or dripping), 4 ozs. fruit (currants, sultanas, dates, or prunes), 1 teaspoonful mixed spice, 1 egg (or dried e SS); 1 tablespoonful treacle, 1 teaspoonful baking powder. Place the potatoes and ground rice in a mixing bowl; make a well in the centre. Into this put the chopped fat, fruit, mixed spice, egg and treacle. Beat all thoroughly for a few minutes. Lastly add the baking powder and mix well. Put into a greased mould. Bake in a moderate oven for 45 minutes or steam for 1J hours. A cake tin or pie dish or basin could be used. Turn out and serve with a custard sauce. Note. — If dates or prunes are used they should be stoned and chopped finely. Currants and sultanas must be well washed before using. Lemon Pudding. 8 ozs. cooked and sieved potatoes (cold mashed potatoes can be used), 2 ozs. ground rice, 1J ozs. fat, 1 tablespoonsful golden syrup, the rind and juice of 1 lemon, 1 egg (dried), 1 teaspoonful baking powder, I tablespoonful milk. Put potatoes ana ground rice in a mixing bowl, make a well in the centre. Grate the rind and squeeze the juice of the lemon; put into the well. Add the syrup, the egg well beaten, the fat melted, and the milk, and beat all well together. Add the baking powder and pour into a prepared mould. Bake for 45 minutes in a moderate oven. Turn out and serve with a jam sauce, or a clear lemon sauce. Chocolate Pudding. 8 ozs. cooked and sieved potatoes, 2 ozs. ground rice, li ozs. fat, 1 tablespoonful treacle, 1 teaspoonful cocoa, 1 egg (dried), 1 teaspoonful baking powder, 2 tablespoonsful milk. Put the potatoes and ground rice in a mixing bowl, add the cocoa, melted fat, treacle, egg, and milk. Beat up thoroughly. Lastly add the baking powder, and mix well. Put into a greased tin or basin, and bake in a moderate oven for 45 minutes or else steam for 1J hours. Turn out on to a hot dish and serve with a, chocolate sauce poured over the pudding. Cinnamon Biscuit Pudding. 2 ozs. sieved potato, 2 ozs. biscuit meal, i oz. melted fat, 1 oz. sugar, 1 heaped up teaspoonful cinnamon (ground), j teaspoonful baking powder, 1J gills of milk and water. Mix the potato, meal, sugar, and cinnamon together. Add the melted fat, milk and water and beat together thoroughly. Lastly add the baking powder, put it in a greased pie dish and bake in a moderate oven for J hour. INDEX Analysis of potato, 19 Apterite, 75 Arsenate of lead, 103 Ayrshire, 23, 37, 45, 68 Basic slag, 26, 29 Bastard trenching, 58 Bichloride of mercury, 98 Black scab, 37, 96 Blight, 12, 91 Boom, potato in 1902-4, 14 Bordeaux mixture, 13, 93, 94 Botany of the Potato, 16-21 Boxing of sets, 36, 42-45 Chemical constituents of potato, 19, 26 Chloride of potash, 30 Clay soil, 22 Colorado beetle, 102 Copper soda mixture, 93, 95 Corrosive sublimate, 98 Cross fertilisation, 12 Cultivation, after planting, 62-66 ; on the farm, 71 Cuttings, propagation by, 48 Cat tubers, propagation by, 46 Digging land, 58 Digging potatoes, for seed, 39 ; digging the crop, 64-66 ; on the farm, 72 ; by machines, 88-89 Disease resisting, 13, 37, 80 Diseases, 90-104 Distribution of potato growing in N.Z., 67 Drainage, 24, 25 Early potatoes, to raise, 49 Earthing-up, 63, 72 Experiments to show effect of humus, 28 ; effect of various manures, 33-4 ; effect of locality and climate, 38 Export, 8 False wire-worms, 101 Famine, Irish, 12 Farm cultivation, 39, 67-73 Farmyard manure, 26-28, 33, 58, 68, 70 Forcing the potato, 74-77 Fowl manure, 32 Fungicides, 93 Fungoid pests, 90-99 Garden cultivation, 55-66 Greenhouse, use of, 74-76, 78 Greening sets, 13, 36, 40 History, 10 Immature sets, 13, 36 Implements, 86-90 Import, 14 Inch Clutha, 24 Insect pests, 99-104 Irish blight, 91, 98 Jersey, 37 Kainit, 30 Lazy beds, planting in, 66 Leaf curl, 98 Lime, 32, 101 Loams, 22 Machines, 86-90 Manures, 25-35 Manuring, 56 Mica schist soils, 24 Millipedes, 101 Muriate of potash, 35 Nauru Island, 29 New potatoes from old ones, 77 Nitrate of soda, 26, 75 Nitrogenous manures, 31 INDEX Oamaru soils, 24 ; potatoes, 37 Paris green, 103 Patterson, William, 12, 13 Peaty soils, 24 Phosphatic manures, 29 Phosphoric acid constiuent, 20 Phytopkthora injestans, 13, 91 Planting potatoes, 59-62 ; in farm cultivation, 69-71; by machines, 86-88, Ploughing, 89 Pollination, by hand, 50 Potash and potatoes, 20 Potash manures, 29 Potato beetle or potato bug, 103 Potato moth, 103 Preparation of soil, 55-58 ; in farm cultivation, 68 Propagation, 35-54 Raleigh, Sir Walter, 10 Recipes, 105-114 Reproduction, methods of, 17 Royal Society, 12, 14 Sandy soil, 23 Seaweed as manure, 23, 26, 28 Seed selection, 9, 36 Single eyes, propagation by, 46 Slugs, 101 Soils, 21-25 ; preparation of, 55-58 Solanaceae, 16 Soot, 31 Sorters, potato, 89-90 Sowing the seeds, 52-54 Spirit, manufacture of, 8 Sprayers, 88 Spraying, 9, 13, 94 Sprouting sets, 13, 36, 41 Starch, production of, 8 ; product of assimilation, 17 ; produced by grating potatoes, 18 Storing sets, 41 ; storing the garden crop, 66 ; storing farm crop, 73 Sulphate of iron, 30 Sulphate of potash, 30 Superphosphate, 26, 29, 33, 75 Tools, 86-90 Trenching, 56 Varieties, 13 ; raising new, 49 ; for forcing, 77 ; 79-85 Vegetative method of reproduc- tion, 36, 49 Wart disease, 37, 96 Wire-worms, 99-101 Wood ashes, 31, 75 Printed by Whitcombe and Tombs Limited. 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