CHILDREN'S GARDENS 



guano, the excrement of sea-birds, obtained from 

 the shore of Peru and the islands off that coast ; 

 sulfate of ammonia; and nitrate of soda Chili 

 saltpeter. Phosphates are derived chiefly from 

 bones of animals, raw bones, bone-meal, bone- 

 ash, and the mineral phosphates derived from 

 the rock phosphates of South Carolina, Florida 

 and Tennessee. 



For school-garden purposes the soil should 

 be thoroughly treated with a dressing of farm- 

 manure which by decomposition will gradually 

 be available for growing plants and maturing 

 seeds. A complete commercial fertilizer contains 

 nitrogen, phosphoric acid and potash, and will 

 supply food to the plants before the manures 

 are in proper condition for the purpose. It 

 should be thoroughly mixed with the soil and not 

 allowed to be in contact with the seeds and ten- 

 der roots, as it will cause them to decay. A sec- 

 ond or third application may be necessary, but 

 it is bad management to apply large quantities 

 at once more than can be used by plants, as it 

 is soluble, and may be lost by leaching away be- 

 yond the reach of the root systems. The little 

 plantlet in the seed is supplied with organized 

 plant-food stored in the seed for the purpose by 

 the parent plant and utilized in developing root 

 and stem. When roots begin to thread their way 

 through the soil they absorb the soluble elements 



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