20 CIRCULAR 436, U. S. DEPARTMENT OF AGRICULTURE 



This mixture has been used for sweetpotatoes in the South. 



Many other combinations might be cited. Any farmer desiring 

 more complete information on home mixing should write to his State 

 agricultural experiment station or the United States Department of 

 Agriculture. 



USE ON INDIVIDUAL CROPS 



On cotton, in addition to the application of a balanced complete 

 fertilizer before planting, it is a common practice to side-dress the 

 crop about the time the cotton is chopped with sodium nitrate at the 

 rate of 75 to 150 pounds an acre. 



Beneficial results are often obtained on corn, in the Southeastern 

 States, by applying sodium nitrate before the cultivation of the crop 

 ceases, at the rate of 100 to 200 pounds an acre. 



Good results are obtained on small grains, when the nitrate is used 

 in the spring as a top dressing, at the rate of 75 to 100 pounds an acre. 



When well-balanced complete fertilizers are used on truck crops at 

 planting time, sodium nitrate gives good results and stimulates growth 

 when applied periodically during the growth of the crop. 



Sodium nitrate is widely used on fruit trees, especially apples. The 

 amount to use and whether phosphoric acid and potash should also be 

 used will depend on many factors, such as the soil, its cultivation, and 

 the use of cover crops or sod. In orchard sections where it has been 

 found desirable to fertilize, the following amounts of sodium nitrate, or 

 their equivalents in other nitrogen carriers, have been recommended for 

 annual application to apple trees: One-fourth pound on 1- and 2-year 

 trees, one-half to 1 pound on 3-year trees, 2 to 4 pounds on 6- to 10- 

 year trees, and 5 to 10 pounds on 15- to 30-year trees. These amounts 

 are given only as a general guide and must be modified to suit con- 

 ditions. Nitrate is usually applied in early spring — about a month 

 before the blooming period. Since fertilization is only one of the 

 factors to be considered in fruit production and the use of fertilizers 

 is so closely related to proper methods of pruning, cultivating, spraying, 

 and other practices, careful study of the orchard should be made before 

 fertilizers are applied, and the best horticultural authorities who Lave 

 knowledge of local conditions should be consulted. 



Sodium nitrate is satisfactory as one of the sources of nitrogen in 

 mixed fertilizers for use on tobacco. On average soils in the South- 

 eastern States a complete fertilizer containing 3 percent of nitrogen, 8 

 to 10 percent of phosphoric acid, and 6 percent of potash has been 

 recommended. One-third of the nitrogen should be from nitrate and 

 one-third from a high-grade organic source. For seedbeds a complete 

 fertilizer containing nitrate is applied before planting, and often one or 

 more applications of a solution of sodium nitrate is applied later to 

 hasten the growth of seedlings. 



QUALITY OF CROPS 



Aside from the question of increasing the yield of crops, sodium 

 nitrate is often used because of its effect on quality. While insuring 

 the steady growth of many vegetables sodium nitrate may also im- 

 prove their quality, making them more tender and of better color. 

 This especially applies to leafy vegetables, such as lettuce and spinach. 

 Applications to meadows and pastures have been shown not only to 

 improve yield but also to increase the protein content of the crop. 



