62 Home Vegetable Gardening 



all the plant food elements — some seven in number, 

 beside the three, nitrogen, phosphoric acid and 

 potash, already mentioned. In the second, it must 

 hold the moisture in which these foods must be 

 either dissolved or suspended before plant roots can 

 take them up. 



The soil is naturally classified in two ways : first, 

 as to the amount of plant food contained ; second, 

 as to its mechanical condition — the relative propor- 

 tions of sand, decomposed stone and clay, of which 

 it is made up, and also the degree to which it has 

 been broken up by cultivation. 



The approximate amount of available plant food 

 already contained in the soil can be determined sat- 

 isfactorily only by experiment. As before stated, 

 however, almost without exception they will need 

 liberal manuring to produce good garden crops. I 

 shall therefore not go further into the first classifica- 

 tion of soils mentioned. 



Of soils, according to their variation in mechan- 

 ical texture, I shall mention only the three which the 

 home gardener is likely to encounter. Rocks are the 

 original basis of all soils, and according to the de- 

 gree of fineness to which they have been reduced, 

 through centuries of decomposition by air, moisture 

 and frost, they are known as gravelly, sandy or 

 clayey soils. 



Clay Soils are stiff, wet, heavy and usually 



