Fertilizers for Vegetable GroAvers' 



Prof. R. Horcourt, O.A.C.. Gvjelph, Ont. 



UNTIL comparatively recently the 

 fundamental principles underlying 

 the use of fertilizers was not understood. 

 Some of the questions which had to be 

 solved first were: What is the food of 

 plants? and, What is the source of that 

 food? Further, in order that fertilizers 

 be intelligently and economically used, 

 it is essential that some definite knowl- 

 egde be gained regarding the food re- 

 quirements of different plants and the 

 power which they possess of appropri- 

 ating these food substances. It is also 

 necessary that something be known re- 

 garding the quantity of food materials 

 that are available to the plant, and the 

 particular part each food constituent 

 plays in plant development. These, to- 

 gether with an intimate understanding 

 of the composition and availabihty of 

 the constituents of a fertilizer, and many 

 other points, must be, at least partially, 

 understood before fertilizers can be in- 

 telligently applied. 



Given that the soil is in fair condition 

 and that the cultivation will be thorough, 

 there are certain fundamental facts con- 

 cerning the needs of the soil and crops 

 and the nature of the fertilizers that are 

 not difficult to understand, and atten- 

 tion to which will greatly increase the 

 likelihood of success. 



All soils will not contain or retain 

 plant food to the same extent. -As a 

 rule, clay soils hold that which they 

 receive better than sands, and thus do 

 not suffer so much from the leaching 

 action of water; on the other hand, the 

 sands may be more liable to lose plant 

 food in the drainage water, but they 

 also give up that which they have to 

 plants quicker than the heavy soils. In 

 both classes of soils and all the inter- 

 mediate types, an abundance of humus 

 is essential. 



Regarding the plants themselves they 

 differ in the range of root, period of 

 growth, purposes for which they are 

 grown, and in their power of attacking 

 insoluble constituents of the soil v^'ith 

 which they may come in contact. As 

 a general rule, the greater the depth and 

 range of root a plant has, the less need 

 there is of supplying the ash constituents 

 for that crop, as it can gather its food 

 over a very wide area. The length of 

 the growing period also has a very mark- 

 ed influence on the nature of the ferti- 

 lizer which a plant will require. A crop, 

 such as barley, requires its food in a 

 form more readily available than oats, 

 for its period of growth is shorter and it 



♦Extract from a paper read at the first annual 

 convention of the Ontario Vegetable Growers' 

 Association, held last November at the time of 

 the Ontario Horticultural Exhibition. 



gathers its food almost entirely from the 

 surface soil. 



Such crops as the legumes have com- 

 paratively little difficulty gathering all 

 the nitrogen they need, because, through 

 the aid of certain minute organisms pres- 

 ent in most solids, the immense supply 

 of nitrogen in the atmosphere is avail- 

 able to them; but, on the other hand, 

 they have difficulty in getting the 

 amount of potash they require. Root 

 crops, such as mangolds, turnips, car- 

 rots and beets cannot make ready use 

 of the insoluble mineral constituents of 

 the soil. Hence, in order to insure full 

 crops, they must be supplied with avail- 

 able food in which phosphates should 

 predominate for turnips and nitrogen 

 for mangolds and carrots. 



Another group of plants is distin- 

 guished as a class not so much because 

 of their peculiar habit of growth as be- 

 cause of the objects of their growth. 

 This class includes lettuce, beets, aspar- 

 agus, celery, radishes, in fact all plants 

 that are marketed in immature form. 

 One of the most important points in 

 raising these is to secure rapidity of 

 growth, and thus to insure high quality, 

 which is measured largely by their suc- 

 culence. In order that this may be ac- 

 complished they must be supplied with 

 an abundance of available plant food, 

 and since nitrogen is the one element 

 that more than any other encourages 

 and stimulates leaf and stem growth, 

 its use is especially beneficial to all of 

 these crops. They must not lack this 

 element in any of their growth, though, 

 of course, a sufficiency of the ash con- 

 stituents must be supplied in order that 

 the nitrogen may be properly utilized. 

 Because of their high commercial value 

 the quantity of plant food applied may 

 be greatly in excess of that for any other 

 group of plants. 



It is impossible to give general in- 

 formation concerning the upe of fertiliz- 

 ers that will apply well under all circum- 

 stances. On soil in good condition, it 

 is safe to apply good dressing of readily 

 available nitrogen to all crops that pro- 

 duce large leaf and stem growth and are 

 harvested in the immature state. For 

 the legumes, which can gather their own 

 nitrogen, and potatoes, which use up 

 large amounts of potash, potassic man- 

 ures can safely be recommended, and 

 for roots, and particularly for turnips, 

 phosphoric acid is the dominant fertil- 

 izer. It is not meant that only those 

 particular constituents should be applied 

 for the other fertilizer constituents are, 

 up to a certain point, just as important. 



If the soil is in a high state of cultiva- 

 tion or has been manured with natural 

 products, as farmyard manure, they 



may be used singly to force a niaxinmm 

 growth of the crops. For worn-out soils, 

 possibly the best practice would be to 

 apply with what farmyard manures may 

 be available, a liberal supply of mineral 

 constituents in the cheaper forms, such 

 as ground bone, tankage from pork pack- 

 ing establishments, ground phosphates, 

 and basic phosphate for phosphoric acid, 

 and the crude potash salts, not forgetting 

 wood ashes for potash. The phosphoric 

 acid and potash forms fixed compounds 

 in the soil, and are, therefore, not likely 

 to be leached out, provided the land is 

 continuously cropped. Nitrogen should 

 be applied chiefly as nitrate of soda, 

 because in this form it is immediately 

 useful, and thus may be apphed in frac- 

 tional amounts, and at such times as to 

 best meet the needs of the plant at the 

 different stages of growth, with a rea- 

 sonable certainty of a maximum use by 

 the plants. 



In conclusion, it cannot too strongly 

 be urged that, while fertilizers intelli- 

 gently used may be a source of profit to 

 the fruit grower, and especially to the 

 vegetable grower, carelessly used, they 

 may be a source of great loss. Thev can 

 never take the place of cultivation; in 

 fact, it is only in conjunction with the 

 most thorough cultivation that thev will 

 prove profitable. 



Forcing Vegetables 



W. T. Macoun, Ottawa, Ont. 



In The Horticulturist last winter Mr S. 

 Ward Kennedy, of Leamington, had an article 

 on Early Vegetables. Why not go further and 

 bring vegetables to maturity under glass in 

 winter? I am interested in this question, but 

 only as an amateur, and I trust I am not ask- 

 ing an absurd question. Given a properly con- 

 stnicted, ventilated and heated greenhouse, 

 proper soil, fertilizers and attention, why could 

 - our growers not fill with their produce the stalls 

 of our shops that in winter are supplied with 

 foreign vegetables? — M. W., Hamilton. 



The principal reason why Canadians 

 do not grow winter vegetables to supply 

 the home market is that the winters are 

 so severe that the cost of heating pre- 

 vents successful competition with vege- 

 tables produced in the south. It is grat- 

 ifying to know, however, that tomatoes 

 are being more largely grown in Canada 

 in winter, and, we believe, with fair 

 profit. Lettuce, radish, and some cu- 

 ctimbers are also grown. In southern 

 Ontario, where the winters are compar- 

 atively mild, the growing of vegetables 

 in winter is receiving considerable at- 

 tention. 



