12 
GARDENING IN THE SOUTHWEST 
Amount 
to Use 
Contents 
Formulas 
FERTILIZERS 
Many people advocate the use of commercial fertilizer because 
it does not introduce weeds, undesirable grasses, worms, etc., but in 
heavier soils it must have ground peat (or some similar loosening 
element) used in combination with it. However, where the soil has 
reached a desired tilth, commercial fertilizer can be of great value, 
although its benefits usually do not last more than a season. Gen¬ 
erally speaking, the amount to use is about one pound to every 
twenty square feet. 
All commercial fertilizers are composed of materials that con¬ 
tain varying portions of nitrogen, phosphorus and potash. To 
use them to the best advantage, the specific requirements of the 
soil to be enriched must be understood, that its deficiencies may 
be overcome. Treatises on soil give a number of interesting meth¬ 
ods of determining what is lacking, called "soil tests”, but a gen¬ 
eral knowledge of the character of the prevailing type of soil 
makes this rather difficult work usually unnecessary. 
Commercial fertilizers are sold under many trade names. The 
best grades state an analysis of the content formula on the out¬ 
side of the package, usually designated by a set of numerals thus, 
6:8:4 means there are six parts of nitrogen, eight parts of phos¬ 
phorus and four parts of potash (nitrogen, phosphorus and potash 
always being given in the order named) presenting at a glance 
the information desired. 
OKLAHOMA SOIL CONDITIONS 
"A very simple statement in re¬ 
gard to soil conditions in Oklaho¬ 
ma would be that in the east half 
of the state the major portion of 
the soils are deficient 
in phosphorus and this 
should be added to all 
soils in order to make 
conditions more favor- 
