WINDOW GARDENING 



cially those containing much decaying vegetable 

 matter, improve the physical properties of the 

 soil. Their use renders the soil more open and 

 porous, a condition allowing a ready movement 

 of air and water, a matter of great importance 

 in plant growth. Natural manures also aid in 

 retaining the moisture. 



Chemical fertilizers or manufactured plant- 

 foods merely add to the fertility of the soil and 

 as a rule they do not modify its physical prop- 

 erties. 



NATURAL MANURES SHOULD BE WELL 

 ROTTED 



Natural manures should never be used in 

 potting soils except in a well-rotted state. 

 Where fresh manure is used, fermentation may 

 take place and prove injurious to the plants. 

 Manures when rotting undergo a process of fer- 

 mentation which makes the plant-foods which 

 they contain readily available. 



The use of any manure that has become over- 

 heated in decaying should be carefully avoided 

 as it has lost its value. 



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