FERTILIZERS 



taken not to use too much nitrogen at first, as 

 the plants are liable to go to leaves, but after the 

 head has begun to take shape the nitrogen may 

 be applied in a form immediately available, as 

 nitrate of soda. 



Lettuce should be stimulated in its develop- 

 ment by an abundant application of nitrogenous 

 food. Sow seeds in rows one inch deep, twenty- 

 five to fifty seeds to a foot, and cover with one- 

 fourth to one-half of an inch of fine soil and 

 firm with the hand or the hoe. 



Radishes require rich friable soil, heavily 

 manured and thoroughly mixed. The quick- 

 growing varieties mature in from three to six 

 weeks and should be used before they become 

 pithy. Sow in drills an inch deep, ten to eighteen 

 inches apart and cover with one-half of an inch 

 of soil and carefully firm. 



Peas should be planted as soon as the soil 

 can be worked, in well-drained sandy soil, in 

 double rows, in trenches four to six inches apart. 

 Fill in the trench as the peas grow. In heavy 

 soils the seeds should be within an inch of the 

 surface. They acquire nitrogen through the 

 agency of nitrifying bacteria and require phos- 

 phoric acid and potash. To secure a continued 

 season of production, the vegetative parts, the 

 roots, stem and leaves, must be stimulated by 

 nitrogenous food. 



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