SUPPLYING THE HEAT 



escapes during the heating process is of great 

 benefit to the growing crops, while from other 

 material there is no such benefit substantially 

 nothing but the heat is derived. Steam has been 

 applied to hot-beds, but with no good results as 

 yet. 



Radishes require less heat than lettuce, just 

 as a crop of young cauliflower or cabbage requires 

 less heat than tomatoes, egg-plants, or others of 

 a tropical nature. For radishes, a cart-load of 

 manure, containing thirty-six feet, would be suffi- 

 cient for nine feet of bed, or three sashes, and 

 should be covered with one foot of loam. For 

 forcing cucumbers more heat is required than for 

 lettuce according to the season. In any case, 

 the bed should stand a day after it is prepared, 

 to allow the soil to heat through; it is then ready 

 for seeds or plants. 



The quantity of heating material to be used 

 will not however, depend entirely upon the crop 

 to be grown; we must also take into account the 

 season of the year when it is to be started. With 

 lettuce, for instance : if the crop were to be planted 

 in December, a foot of fresh manure would be 

 necessary; while in February or March one-half 



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