POTATO 



209 



if light and with little humus, the ground will be too 

 dry ; if the subsoil is hard, there will be poor drainage, 

 and the roots, which sometimes penetrate to a depth 

 of four feet, cannot go so deeply as they should. Soil 



r 



Fig. 100. A hill of Potatoes in stiff soil. The tubers are too near the 

 surface. The old-piece is at A. 



which with good surface-cultivation will keep its mois- 

 ture through a dry spell and which in a wet season will 

 not hold standing moisture is best for Potatoes. If 

 there is a choice of soils, sow early Potatoes on the 

 lighter, the main crop on the heavier. 



The soil should be rich. Humus, if supplied in the 



