Fertilizers 



43 



Plant food is of as many kinds, or, more accurately 

 speaking, in as many forms, as is food for human 

 beings. But the first distinction to make in plant 

 foods is that between available and non-available 

 foods — that is, between foods which it is possible 

 for the plant to use, and those which must undergo 

 a change of some sort before the plant can take 

 them up, assimilate them, and turn them into a 

 healthy growth of foliage, fruit or root. It is just 

 as readily possible for a plant to starve in a soil 

 abounding in plant food, if that food is not avail- 

 able, as it would be for you to go unnourished in the 

 midst of soups and tender meats if the latter were 

 frozen solid. 



Plants take all their nourishment in the form of 

 soups, and very weak ones at that. Plant food to be 

 available must be soluble to the action of the feeding 

 root tubes ; and unless it is available it might, as far 

 as the present benefiting of your garden is concerned, 

 just as well not be there at all. Plants take up their 

 food through innumerable and microscopic feeding 

 rootlets, which possess the power of absorbing 

 moisture, and furnishing it, distributed by the plant 

 juices, or sap, to stem, branch, leaf, flower and fruit. 

 There is one startling fact which may help to fix 

 these things in your memory : it takes from 300 to 

 500 pounds of water to furnish food for the build- 

 ing of one pound of dry plant matter. You can see 



