THE GARDEN PRIMER 



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\ to 3 

 parts potash. Such a fertilizer will meet all require- 

 ments of the average garden, especially if the soil is 

 treated with lime first. Lime is not a fertilizer 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- 

 dients are important to know and remember, for even 



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