COTTON FERTILIZERS 321 



available phosphoric acid, and 2 per cent of potash. This 

 is spoken of as a 10-2-2 guano. 



289. Advantages of the home-mixing of fertilizers. 

 If the farmer decides to buy the separate materials and 

 do his own proportioning and mixing, he usually purchases 

 cotton-seed meal, acid phosphate, and kainit. If he 

 wishes to make a more concentrated fertilizer, that is, 

 one of higher grade, he may buy the nitrogen in the form 

 of nitrate of soda, or sulfate of ammonia, and the potash in 

 the form of muriate or sulfate of potash. Those farmers 

 who understand how to mix fertilizers find that it is much 

 more economical to do so than to buy the average ready- 

 mixed guano. The advantage of home-mixing are the fol- 

 lowing : 



(1) The mixture made at home usually costs several 

 dollars less per ton than a factory-mixed fertilizer of 

 exactly the same composition. 



(2) Home mixing permits the farmer to suit the fer- 

 tilizer to the particular soil on which each lot is to be ap- 

 plied, and to adapt the fertilizer to the different crops. 

 For example, in purchasing a complete ready-mixed fer- 

 tilizer, he applies this to all soils and all crops; yet the 

 nitrogen in it is not needed by legumes, such as cowpeas 

 and peanuts ; and the potash in it may not be required by 

 any crop on some clay soils. In making his own mixture 

 the farmer would omit the nitrogen in the one case and 

 the potash in the other, and thus save their cost. How- 

 ever, farmers who do not understand how to suit the fer- 

 tilizers to the soil and the crop find it advantageous to 

 use a factory-mixed guano. Its one slight advantage con- 

 sists in being somewhat more evenly mixed. 



