CHAPTER VII 
COMMERCIAL FERTILIZERS 
104. Necessity of commercial fertilizers. — It is not 
uncommon to find market gardens managed successfully 
without the use of commercial fertilizers. In all such 
cases stable manures and perhaps night soil are applied 
in liberal quantities. Although it is possible to make 
large profits when fertilizing with manures only, it is 
doubtful whether there are any instances when commer- 
cial fertilizer in some form could not be used to ad- 
vantage. Manure is an unbalanced ration; it is richer 
in nitrogen than in mineral elements and there is likely 
to be a surplus and, therefore, a waste of nitrogen when 
it is applied without corresponding additions of potash 
and phosphoric acid. 
The most forceful argument for the use of commercial 
fertilizers is the inadequate supply of animal manures. 
While hundreds of market gardeners near the cities de- 
pend mainly upon stable manures, thousands of truckers 
remote from the great sources of supply must resort to 
the use of commercial fertilizers in order to secure maxi- 
mum returns. 
There are other reasons for the use of commercial fer- 
tilizers. Stable manure must undergo changes before it 
is accessible to plants, while some of the commercial fer- 
tilizers are immediately available when incorporated with 
moist soil, a characteristic which gives chemical ferti- 
lizers a great advantage over stable manure, for it is pos- 
sible to mature crops in less time by their use than can 
be done with manure alone. Rapid growth is of immense 
importance in commercial vegetable gardening. There- 
fore, with the aid of commercial fertilizers the gardener 
