FERTILIZING AND FERTILIZERS 



the stupendous work being carried on by all the silent 

 green things that we give scarce a thought to in the 

 long, drowsy summer days! 



All fertilizers present, in different forms, three 

 essentials — phosphoric acid, potash and nitrogen. The 

 latter is the last of those thirteen chemical elements 

 mentioned which feed vegetation — the one which 

 comes principally from decaying organic matter in 

 the soil — and in some respects it is the most important 

 of all. Unfortunately it is the one most easily lost — 

 nitrates being very soluble — through washing out, or 

 exhausted in other ways; therefore it is the one which 

 should be applied only in sufficient quantity for the 

 immediate use of the plants to be grown, and just at 

 the proper time for their needs. It is usually well to 

 wait until they are above the ground. 



Surplus phosphoric acid and potash, on the con- 

 trary, will usually remain in the soil until succeeding 

 crops use them up, so it does not matter so much if 

 these are applied in excess. They are not wasted. 



What is known as a complete fertilizer is a com- 

 bination of these three in the proportion generally of 

 I part nitrogen, 2 parts phosphoric acid and 2 J to 3 

 parts potash. Such a fertilizer will meet all require- 

 ments of the average garden, especially if the soil is 

 treated V/ith lime first. Lime is not a fertiHzer in 

 the strictest sense, but it sweetens the soil as well as 

 helps to bring about physical and other changes that 

 make plant food available. 



The sources of each of these three fertilizer ingre- 



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