WINDOW GARDENING 



velop SO readily in sandy soils — a fact of great 

 importance in growing cuttings and seedlings. 



CLAY 



A clay soil contains from lo to 20 per cent, of 

 sand and, without the admixture of additional 

 sand, makes a poor soil in which to grow plants. 

 Although it contains an abundance of nutrient 

 substances and absorbs a great deal of water, 

 both are held so tenaciously by the soil particles 

 that they are taken up with difficulty by the 

 plant. The roots, also, have difficulty in pene- 

 trating the soil, owing to' the compactness due 

 to the extremely small size of the soil particles. 

 Mixed, however, with some substance that will 

 increase its porosity it makes an ideal soil. 



HUMUS 



Humus is decayed vegetable matter and may 

 be divided into two classes — vegetable mold and 

 peat. Vegetable mold or leaf mold, as it is 

 commonly called, is composed of plant remains 

 decayed in comparatively dry earth, as in the 

 surface coverings of the forests. Peat, on the 



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