CHAPTER VII. 



MANURES FOR THE GARDEN. 



II. COMMERCIAL FERTILIZERS THEIR VALUE AND USE. 



" Prove all things ; hold fast that which is good." 



[OMMERCIAL fertilizers are coming more and 

 more in general use with market gardeners, and 

 are now quite extensively substituted for stable 

 manure — and that not without good reason. If 

 we examine a good high-grade commercial fer- 

 tilizer, analyzing 5 per cent, available nitrogen, 

 8 per cent, phosphoric acid, and 8 per cent, potash, 

 we will find that one ton of it contains, besides 

 less valuable ingredients : 



100 lbs. nitrogen, estimated at 16 cents, - $16 00 



160 " phosphoric acid, at 6 cents, - - 9 60 

 160 " potash, at 5 cents, - - - - 8 00 



Total, $33 60 



Such a fertilizer probably retails at $^^ to $40 per ton, and 

 is fully worth it. All this large amount of plant food, and per- 

 haps one-half more, can be drawn in a single load, while it will 

 take ten such loads of stable manure to supply the same amount 

 of nitrogen (and that in a far less available condition), sixteen 

 such loads to supply the same amount of potash, and forty to 

 supply the same amount of phosphoric acid. On an average, 

 therefore, the substitution of the commercial fertilizer for barn- 

 yard manure will save 14-15 of the labor and expense in hauling 

 and in application, besides all the additional trouble and labor 

 of composting. 



In a further comparison of the two manures we come to the 

 following results : A moderately liberal application of compost 

 requires 50 tons to the acre. This means vhe application of 400 

 lbs. of nitrogen, 500 lbs. of potash, and 200 lbs. of phosphoric 

 acid, at a costof^ 100 to ^125, not taking in consideration the large 

 expense of handling and applying it. 



Men most liberal in the use of commercial fertilizers apply, 

 and recommend to use, one ton per acre, at a cost of less than 



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