20 Subtropical Vegetable-Gardening 



Acidity of Florida soils. 



The soils of Florida are for the most part made up of 

 siliceous particles, and have no available alkali or base to 

 neutralize any acidity. In a few cases in which an 

 abundance of limestone occurs in the surface soil, it is a 

 corrector of acidity, but by far the larger percentage of 

 the sandy soils are acid. 



Florida muck soils are nearly all acid, there being very 

 few exceptions. These are not only acid, but very strongly 

 so, and frequently require a very large amount of ground 

 limestone to correct the acidity. 



In addition to the fact that most Florida soils are natu- 

 rally acid, this condition is intensified by some of the 

 fertilizers, especially when large amounts of sulfate of 

 ammonia are used. When such materials are broken up, 

 as they are in the process of being made available to plants, 

 the acid radical is left in the soil. 



How to test for soil acidity. 



Soil may be tested readily for acidity. This can best be 

 done in the field. Procure strips of litmus paper from the 

 drug-store, of both kinds, pink and blue. In using this 

 litmus paper, care should be taken that the fingers do not 

 touch it, since the perspiration from the hands is usually acid 

 enough to turn the blue to pink, and in testing soil after the 

 paper has been handled a false reaction might occur. The 

 soil to be tested must not be too dry. A small amount 

 of soil may be taken up, and if it can be pressed into a 

 good ball it usually contains enough moisture to show the 

 reaction. Break the ball of soil open and place two strips 



