FERTILIZATION. CULTIVATION. IRRIGATION 45 



NITROGENOUS CROPS. Nitrogen is the most ex- 

 pensive of all fertilizing elements, but if the gardener 

 can not afford to buy enough of it (in stable manure 

 or nitrate of soda, etc.) he can supplement his supply 

 by producing it right at home. How? By the simple 

 process of growing some crop which has the ability 

 to extract nitrogen from the air and store it up in 

 the form of nodules or lumps on its roots. Plants 

 of this kind are called "legumes" ; the principal ones 

 are : Clover, vetch, beans, peas and cowpeas. Any 

 one of these, if planted as a cover crop or as a crop 

 to plow under, adds nitrogen to the soil and greatly 

 improves the land. This process is called "green 

 manuring," and if the garden is not full of humus 

 and if stable manure can not be had to supply nitro- 

 gen cheaply, it m?y pay you to spend a preliminary 

 season in the growing and turning under of such 

 crops supplementing the nitrogen thus obtained by 

 broadcast applications of potash and bone meal in the 

 spring, and lime in the fall. (NOTE: Oats, rye, etc., 

 furnish humus but no nitrogen ; legumes furnish 

 both.) 



NITRATE OF SODA. Much is heard about the quick 

 results produced by this nitrogenous fertilizer, but 

 unless it is handled with great carefulness I can not 

 recommend its use. Harriet says that it is "more 

 like a stimulant than a food." It must be applied in 

 small doses often. Yes, and with care or you'll kill 

 your plants. About 100 pounds at a dose to the acre 

 is usually enough, and, generally speaking, it should 

 not come in direct contact with plants. (Nitrogen 

 may also be purchased in the form of dried blood, 

 guano, tankage, cotton seed meal, sulphate of am- 

 monia, etc.) 



LIQUID MANURE. This, like nitrate of soda, is a 



