60 MANAGEMENT OF THE FORCING-HOUSE. 



is required to fill the bench 8 inches deep with soil. Ex- 

 periments are now in progress to determine whether the 

 use of peat is necessary. About 10 pounds of commercial 

 fertilizers are needed for this bench space, costing, at pres- 

 ent ruling ton rates, less than 21 cents. The cost of these 

 things is to be compared with the cost of providing a con- 

 siderably greater weight of rich compost containing a large 

 relative amount of stable manure. In very many cases, the 

 cost of filling the benches with the artificial soil must be 

 very much less than the cost of filling them with rich garden 

 soil. 



"The greatest expense in running a forcing-house is the 

 artificial heat required, and for this reason, quick growth 

 and early maturity are extremely desirable. Regarding the 

 relative availability of the potash and phosphates in compost 

 and in commercial fertilizers, we know little, but it is very 

 certain that the nitrogen of composts is slowly available as 

 compared with the nitrogen of nitrates. Our tomato tests 

 showed, too, very clearly, that plants in natural soil made 

 much slower growth and were slower in fruiting than those 

 in artificial soil supplied with nitrates. Though the former 

 were set fully three weeks earlier, both began fruiting at the 

 same time." 



The general summary of all the results of fertilizing the 

 tomatoes is as follows : 



"i. A forcing-house tomato crop yielding about two 

 pounds of fruit for each square foot of bench room, takes, 

 in the vines and fruit, for every hundred square feet of 

 bench space, not less than : 



Grams. Lbs Ozs. 



Nitrogen !68 Equivalent to Nitrate of soda 2 5 



Phosphoric acid . . 65 " " Dissolved bone black o 13 



Potash 362 " " Muriate of potash I 9 



"Of this from a fourth to a fifth only is in the vines. 



" 2. To enable the plants to get these fertilizer elements 

 as required, there should be a large excess of them in the 

 soil, perhaps double the quantity given above. 



