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Fertilizers 



with vegetable matter containing nitrogen. On such 

 soils, additional applications are very important, and 

 nitrate of soda is one of the best forms to use, as it is ab- 

 sorbed freely by the roots, encouraging an early and vigor- 

 ous growth of plant and a normal development of fruit. 

 Slow-acting organic forms of nitrogen, on the other hand, 

 frequently begin to feed the plant and cause its rapid 

 growth when the energies should be concentrated in the 

 growth and maturity of fruit. Fertilizers that have proved 

 very excellent are those which contain a relatively smaller 

 amount of nitrogen than is required for early tomatoes, 

 and are richer in phosphoric acid and potash. 



A study of the composition of both the fruit and vine 

 of the tomato will serve to guide us in this respect, though 

 the amounts and proportions of food removed by any crop 

 are not absolute guides, inasmuch as the soil may furnish 

 more of one constituent than another, and because the 

 plant may have the power of acquiring certain of its con- 

 stituents more readily than others. The analyses of the 

 fruit and vines of tomatoes show that one ton contains: 



Ten tons of the fruit, with the accompanying vines, 

 which would probably reach four tons, would contain 

 57 pounds of nitrogen, 16 of phosphoric acid and 94 of 

 potash. On a good soil, therefore, which without manure 

 would produce five or six tons, there should be added a 

 sufficient excess of the constituents to provide for a maxi- 

 mum production, and the materials should be relatively 



