352 MANURE AND COMMERCIAL FERTILIZERS 



important to keep the garden soil slightly alkaline, and this 

 requires the occasional use of lime. Many of the soils 

 are infertile because of acidity which prevents the growth 

 of the soil bacteria that are essential to decomposition. 

 Liming also promotes the growth of bacteria and makes plant 

 food available. A thousand pounds of . air-slacked lime 

 to the acre is usually sufficient on most soils. This should 

 be applied broadcast over the soil and harrowed in, care 

 being taken not to mix it with horse manure, as it releases 

 the nitrogen in the manure. If applied in the spring, it 

 should be spread two or more weeks before seeding. 



Mixing of Fertilizers. For the home garden, it is usu- 

 ally most convenient to purchase high-grade commercial 

 fertilizers already mixed. In commercial vegetable grow- 

 ing, there are many advantages in the home mixing of 

 fertilizers. The grower can compound the mixture in 

 such proportions as best suits his particular needs, and 

 thus know the kind and amount of each fertilizer used. 



Fertilizers may be mixed upon any tight floor. If 

 nitrate of soda or potash salts are used, they should be 

 crushed fine before mixing. The light materials, as dried 

 blood or tankage, should be put on the bottom of the floor 

 and the other materials spread over them. The materials 

 are then thoroughly mixed by shoveling the pile over 

 several times. After mixing, the fertilizer should be bagged 

 and kept in dry storage until ready for use. One of the 

 chief advantages of buying factory-mixed fertilizers is 

 that they are more uniformly mixed. 



Cover Crops. Many truck growers find the practice 

 of cover-cropping the most economical method of supply- 

 ing humus. Sometimes this cover crop is left to grow for 

 a year or more and forms one of the crops of a rotation. 



