1 8 HOW TO MAKE SCHOOL GARDENS 
use a farm manure, on account of the 
physical help to the soil in aiding it to 
retain moisture. An application of ten 
cords to the acre will cover the land 
one-fourth of an inch. This is a fair 
application, although market gardeners 
often use more than double that amount. 
A little additional commercial fertilizer 
in the row will be helpful on the start. 
Sandy soils are most likely to be deficient 
in nitrates, as the latter are soluble and 
are washed through such soils. On heavy 
soils also farm manures tend to lighten 
them. The use of lime on such soils 
(those which crack upon drying) increases 
the growth and healthfulness of plants by 
improving the physical condition of the 
soil and sets free unavailable plant food. 
Wood-ashes also aid in this, besides 
supplying the potash. The lime should 
be used fine, from five to ten barrels per 
acre. For light, spongy soils, high-grade 
commercial fertilizers are as good as any. 
If the crop to be grown is an early matur- 
ing one, commercial fertilizers are best, 
