COMMERCIAL FERTILIZERS IN HORTICULTURE. 169^ 



which determine the farmer's plant food deficiencies. For certain 

 farmers in the Connecticut Valley, whose alluvial soils cry out for 

 potash, to buy the same fixed formula as the Maine farmer, whose 

 granitic soil is, by the processes of weathering, yielding its annual 

 quota of available potash, or for the grain producer, whose 

 environment admits of the successful use of clover in the rota- 

 tion, to purchase as much nitrogen as the farmer located where 

 clover does not thrive, is to adopt a "rule of thumb" method 

 that does not belong to the highest order of farm management. 

 I grant, yes, I do more than this, I assert, that with the horticult- 

 urist, who is engaged in intensive production, the case is different. 

 In the forcing house and garden, conditions are almost if not 

 entirely artificial, so far as it is a question of feeding the plant. 

 Even in the garden, the variations in the natural food supply are 

 obscured by the greater amount of available material supplied by 

 the generous applications of stable and commercial manures. 

 "While we must still depend to an extent upon the chemical 

 activities whose field of action is the rich garden loam and the 

 artificial soil of the forcing house, we are comparatively indepen- 

 dent of those processes of weathering which are of so much 

 importance as a means of fertility in the long rotations of the 

 grass and grain farm. In the production of grass, grain, and even 

 the ordinary hoed crops, the natural capacity of the soil, or its- 

 annual contribution of available plant food is an important, and 

 even a controlling, factor ; but in certain lines of horticultural 

 work it is a minor factor. In horticulture and the forcing of 

 vegetables, the plant is the one thing to be considered, and after 

 we have made the physical conditions and water supply what they 

 should be, we may safely proceed to feed the plant as if its sole 

 supply of nourishment is what we furnish it. 



The considei'ations stated in the foregoing lead me to the 

 conviction then that the fertilizers ordinarily found in the markets 

 are not economically adapted to certain lines of horticultural 

 work. The proportions of ingredients in these goods is such that 

 it is necessary to purchase too much of one in order to obtain 

 enough of others. For use under the conditions to which I have 

 so far confined this discussion, I am convinced that on the 

 average the amount of phosphoric acid used should at least not 

 be in excess of either the nitrogen or potash, or, in other words, 

 for market garden and forcing house use, the proportions of 



