GARDENING 



183 



should be learned besides how plants grow. Such experi- 

 ments as some of the following may be tried even in window 

 boxes, or plant trays (Fig. 103) : 



Determine the influence of depth of planting as sug- 

 gested by Fig. 77. But try it in the garden as well as in 

 the school-room. 



Fig. 103. — A. The roof garden made by children. The city is a place where 



y experiments may be tried. 



B. School garden work; a lesson in thinning plants. (Agricultural Education.) 



Compare two parts of a row with and without dust- 

 mulch methods. 



Try potatoes by the '4evel culture" and the ''hilling up" 

 methods. 



Grow crops that are not commonly raised in the section; 

 perhaps some new legumes, as alfalfa, cow peas, soy beans, 

 or vetch. 



The effects of certain fertilizers or of lime may be tried 



