10 Southern Gardener's Practical Manual 



Sulphate of potash of high grade contains 48 to 51 

 per cent of actual potash. This form is usually pre- 

 ferred to muriate or kainit for tobacco and some garden 

 crops, such as Irish potatoes and other starch- producers. 

 There are other commercial sources of potash, but these 

 are most commonly used. 



RELATION OF SOIL TO PLANTS 



While a very small part of the food of plants is fur- 

 nished directly by the soil, the plant is dependent upon 

 it in many ways. It supports it mechanically in an 

 upright position, and thus exposes its leaves to the in- 

 fluence of the direct rays of the sun. It furnishes a field 

 in which its roots ramify and gather, not only the min- 

 eral or ash elements of its food, but the moisture neces- 

 sary to serve as a vehicle for the transmission of its 

 supplies, both direct and indirect, into its circulation. 



The soil is the storehouse of plant -food, the larger 

 part of which is held in reserve in insoluble compounds 

 awaiting intelligent manipulation to induce such con- 

 ditions as will render its stores available to plants. 

 It is at once a chemical and biological laboratory in 

 which nature's reagents are ever at work producing, 

 by analysis and synthesis, the mysterious metamor- 

 phoses of the material which is there stored for the 

 use of the plant. Chemical changes and bacteriological 

 activity await the skilful manipulation of the intelligent 

 gardener to supply the conditions necessary for the 

 maximum usefulness of these auxiliary forces. It re- 

 ceives and stores the warmth of the sun's rays, husbands 



