FERTILIZERS 



FERTILIZERS 



1227 



before planting. No amount of nitrogen applied in 

 tlie field appears to be able to offset finally and fully 

 tlie disadvantage of the tubers with the low nitrogen- 

 content. This doubtless explains the advantage of 

 early dug potatoes, for seed purposes, as compared 

 with those which are allowed to mature, for the former 

 are usually richer in nitrogen. 



Asparagus. 



Sand}' soil is ideally adapted to the growing of aspara- 

 gus. Nevertheless, whenever it is intended to estab- 

 lish a plantation on land of this character, it is wise to 

 turn under considerable stable manure or else a heavy 

 leguminous crop such as hairy vetch. If this is done, 

 the general soil conditions are rendered much more 

 favorable and the asparagus has a better chance to 

 gain a good foothold. Wherever the land needs liming, 

 some lime should be plowed under and a further appli- 

 cation should be made on the surface after plowing. 

 The land should then be thoroughly harrowed or 

 otherwise tilled. 



Fine ground bone and basic slag meal have been 

 used for asparagus very successfully when worked into 

 the soil at the outset, although the latter is rather better 

 adapted to it on account of the greater availability of 

 the phosphoric acid and the fact that it contains con- 

 siderable lime. 



Some of the best growers of asparagus, on sandy 

 soils, have found that muriate of potash is a better 

 source of potassium than the sulfate. 



In humid regions fertilizers for asparagus should 

 contain a considerable amount of nitrogen in nitrates, 

 though other forms of nitrogen are also particularly to 

 be desired on light soils, such as those usually employed 

 for this crop, because of the danger of the loss of 

 nitrates by leaching. It is obvious that, for top-dress- 

 ing, superphosphate is preferable to any other form of 

 phosphoric acid, because of its greater solubility. An 

 ideal fertilizer for asparagus should contain super- 

 phosphate, potash salts, and high percentages of nitro- 

 gen, a part being derived from nitrates, some from 

 ammonium salts, and also some of it from organic 

 sources. 



Sandy soils are likely to be very deficient in phos- 

 phoric acid; hence, the quantity of this ingredient 

 should be high. The fertilizer should likewise carry a 

 high percentage of potash on sandy soils, excepting 

 in regions in which it is known not to be needed. 

 Although potash is usually the least deficient element 

 in the sandy soils of humid regions, the demand of the 

 asparagus plant on this ingredient of fertilizers is so 

 great as to make its use profitable, whereas on other 

 sandy soils in semi-arid regions, potash might not be 

 required. 



Melons. 



On soils that are very acid, it is imperative to use 

 considerable quantities of lime for canteloupes and 

 muskmelons. Such soils will, nevertheless, produce 

 good crops of watermelons, even if liming is omitted, 

 and heavy liming with slaked or burned lime may, 

 in some eases, even decrease the yield. 



Owing to the fact that these crops are generally 

 grown on light, gravelly or sandy soil, a fertilizer is 

 demanded for humid regions containing a fairly high 

 percentage of nitrogen. This should be represented by 

 nitrates, to a still greater extent by ammonium salts, 

 and a part should be from suitable organic sources. 

 It should ahso contain a high percentage of soluble 

 and immediately available phosphoric acid and gen- 

 erous amounts of potash in order to bring the crop to 

 maturity as rapidly as possible. Plants of this character 

 which have an ex-tensive amount of foliage, usually 

 require high percentages of potash. Special care should 

 be taken to keep the fertilizer from coming in contact 

 with the seed. 



Squashes and pumpkins. 



The common summer .squash, as well as the Hubbard 

 and crookneck varieties, are less in need of liming than 

 canteloupes or muskmelons. Nevertheless, on very 

 acid soils liming is decidedly helpful. These crops are 

 all heavy feeders on nitrogen, a considerable part of 

 which should be in immediately available nitrates and 

 ammonium salts. Moderately high percentages of 

 soluble and available phosjihoric acid are necessary, 

 although the summer squash, at least, responds much 

 less to phosphoric acid and more to potash than the 

 cereals and most other cultivated crops. On this 

 account, the percentage of potash in fertilizers for 

 squashes should be high, excepting, of course, where 

 the soils are already rich in available forms of this 

 ingredient. 



Celery. 



Celery is a crop that will thrive well on slightly acid 

 soils. Nevertheless, where the acidity is great, liming 

 is very beneficial. The quality of this crop depends 

 very largely upon its making a rapid and steady growth. 

 On this account a constant water-supply is one of the 

 most important features connected with its culture. 

 It is of the highest consequence that celery should 

 have a large supply of nitrogen embracing suitable 

 proportions of nitrate nitrogen, ammonium salts and 

 organic materials. Fair amounts of soluble and avail- 

 able phosphates are desirable, and on the muck or 

 peat soils where this crop is frequently grown, espe- 

 cially large quantities of potash should be employed, 

 since this is the fertilizer ingredient which they lack 

 to the greatest e.xtent. The form of potash usually 

 preferred on such soils is the muriate, although fre- 

 quently kainit is said to have given excellent results. 

 Either is perhaps preferable to the high-grade sulfate 

 of potash or to the double manure salt. 



Cucumhers. 



Cucumbers are considerably more in need of liming 

 than squashes. In other respects they should have 

 es.sentially the same fertilizer treatment. Great care 

 should be taken in connection with squashes and 

 pumpkins, as well as with cucumbers, not to allow the 

 seed to come in close contact with the fertilizer, or, 

 indeed, with soil into which large quantities of fertilizer 

 have been introduced. If fertilizer is used in the hill it 

 is well to have it thoroughly incorporated with the 

 soil. Subsequently, this soil should be covered with 

 fresh earth before the seeds are planted. 



Tomatoes. 



The tomato will grow quite well even on soils that 

 are distinctly acid. Nevertheless, moderate liming is 

 often helpful. When tomatoes are grown in green- 

 houses it has been found that very large quantities of 

 lime are helpful, by virtue of lessening the tendency to 

 certain diseases, but the necessity for it is less in the 

 field because of the lower temperatures and less humiil 

 conditions. 



In order to hasten the ripening of this crop, it is very 

 important to have large quantities of soluble and 

 available phosphoric acid, and abimdant potash in the 

 fertilizer. One of the most important features is to 

 have the nitrogen supply so regulated as to bring about 

 at once a rapid and vigorous growth of the plants, but 

 the quantity must not be so great as to prolong the 

 growing period unduly, since this will prevent early 

 ripening; and it is a well-known fact that the early 

 fruit generally sells for a much higher price than that 

 which matures later. Furthermore, a large proportion 

 of the nitrogen should be present as nitrates and 

 ammonium salts which can be readily utilized. It is 

 also desirable to apply the entire amount at the time 

 when the plants are set, or, at least, very shortly after- 

 ward, for if successive apphcations are made at a later 



