Cotntnercial Fertilizers: Their Nature and Value 



Frank T. Shutt, M.A., Chemist, Dominion Experimental Panns 



COMMERCIAL fertilizers are mater- 

 ials, "largely, but not altogether, of 

 the nature of chemical compounds, 

 lat furnish nitrogen, phosphoric acid 

 id potash in a more or less readily 

 mailable form. Their value depends 

 Imply and solely on the percentages of 

 bese elements they contain, and the 

 k'ailability of this plant food. Nitrogen, 

 bosphoric acid and potash are known 

 the essential elements of plant food, 

 ecause it has been found that, of all the 

 ^ements extracted, or absorbed from 

 be soil by crops during their growth, 

 bese three only must be continually re- 

 jrned. Without this putting back of 

 Itrogen, phosphoric acid and potash, a 

 jil's productiveness must be seriously 

 Tected under any system of cropping 

 ^hen the produce is sold. Let us clear- 

 understand, therefore, that the value, 

 »^riculturally and commercially, of a 

 prtilizer is controlled by the amounts 

 ad availability of these forms of plant 

 3d that they contain. In this coun- 

 ry, the term "phosphate" is applied by 

 any people to all kinds of fertilizers, 

 Irespective of their composition. This 

 not right; it should be restricted to 

 bose fertilizers which furnish phosporic 

 cid only, such as superphosphate and 

 asic slag. 



The term "artificial" fertilizer is ob- 

 |ctionable, because it is misleading. 

 the elements of plant food that fertiliz- 

 es furnish, are identical with those of 

 able manures. The crops could not 

 Sstinguish between them. Bread and 

 |e and jelly are prepared foods, but 

 ?t artificial foods, .so likewise fertilizers 

 day be prepared, but not artificial, in 

 Be sense of not being real and normal 

 prms of plant food. 



The term "stimulant," as applied to 

 fertilizer also is misleading. Ferlili- 

 ^rs are not stimulants ; they do not re- 

 ive the plant, giving it temporary 

 Irength. They feed the plant and 

 peir elements are built up into the 

 mt's tissue of root and branch and 

 if and seed. If used rationally — that 

 in conjunction with stable manures, 

 keep up the humus content of the 

 bil — they cannot be likened to the whip 

 the tired horse. "But are they not 

 exhaustive?" I hear some one ask. 

 Sometimes they may be, but again the 

 inswer is that such will be due to ir- 

 : .itional use. 



The crop-producing power of a soil is 

 neasured by, or in proportion to, that 

 ' lement of plant food least abundant, 

 and not by that in greatest abundance. 

 This fact explains why it is that the con- 

 linued use of some one fertilizer, or, 

 lather, fertilizer-ingredient, has what ap- 



pears to be an exhaustive effect. If, for 

 instance, nitrogen only is supplied (as in 

 nitrate of soda) the increased vigor and 

 growth of the crop resulting will extract 

 from the soil larger amounts of potash 

 and phosphoric acid than would other- 

 wise have been the case. The natural 

 stores of available phosphoric acid and 

 potash in the soil are thus depleted, the 

 larger yields at first obtained, rapidly 

 fall off, and the soih is poorer than at 

 the start. This points to the necessity 

 of a rational system in the use of fer- 

 tilizers, and supplying all the necessary 

 elements of plant growth. It is only by 

 such practice, that a maximum yield 

 can be obtained without depleting the 



and every one about to purchase these 

 ready-made, mixed fertilizers should 

 consult that bulletin before buying. It 

 will not be possible for me to say any- 

 thing further regarding them, in case 

 it might be construed into a special com- 

 mendation. One hundred and seventy- 

 three "standard" samples were analysed 

 last year, and obviously to discuss the 

 merits of all would be impossible. 



FERTILIZER INGREDIENTS 



There is no necessity to buy ready- 

 mixed fertilizers. The various ingred- 

 ients can be purchased and the mixing, 

 when necessary or desirable, made with- 

 out any expensive machinery or any 

 special skill. By this home-mixing of fer- 



Prepare now for Fairs and Exhibitioni next Fall. 



The Illustration show.'* a tastefully iirranf:c(l exhibit by tlie Chatham Vegetable GrowerB 

 Association al an AgrioiiUiiral Kxhibitioii last year. 



soil. The point to be remembered in 

 this connection, is that the yield will be 

 proportional to that element of plant 

 food present in smallest amount. It is, 

 therefore, neither wise nor safe to de- 

 pend entirely on any one form of fer- 

 tilizer. 



READY MIXED FERTILIZERS 



A very large number of "ready- 

 made," that is, mixed fertilizers, may 

 be found on the market. These are 

 prepared simply by mixing and grinding 

 certain ingredients that contain nitro- 

 gen, phosphoric acid and potash, with 

 the addition of a "filler" to make 

 weight. Their value is calculated from 

 their composition, that is, from a know- 

 ledge of their percentages of nitrogen, 

 phosphoric acid, and the relative avail- 

 ability of these elements. You will find 

 this information given annually in a 

 bulletin issued by the Dominion Gov- 

 ernment (Inland Revenue Department) 



131 



tilizers, a saving of twenty-five to thir- 

 ty-five per cent, could be easily effected. 

 Further, it would allow of the making in 

 small quantities of several mixtures, 

 with varying proportions of nitrogen, 

 phosphoric acid, anH potash, for the 

 trial or experimental work. This is an 

 important matter ; one that you cannot 

 afford to ignore. There are direct and 

 considerable advantages, therefore, in 

 buying these ingredients, rather than 

 the ready-made fertilizer. The composi- 

 tion and merits of some of the ingred- 

 ients that may be used in compounding 

 fertilizers will be discussed in the next 

 issue of The Canadian Horticulturist. 



Air-slaked lime will free the cabbage 

 plants from worms and not injure the 

 plants. 



Abundant food within easy reach is 

 what plants require in order to make 

 their best growth. 



