RHUBARB 195 
As previously stated, a common plan is to utilize space 
under greenhouse benches for the forcing of rhubarb. 
The success of this plan will be determined largely by 
the temperature which must be maintained for other 
crops in the house. See page 163. Occasionally the beds 
or benches are used for rhubarb, but that space is re- 
garded as more valuable for other crops which require 
more exacting conditions of heat, light and moisture. 
Manure hotbeds are largely employed by market gar- 
deners for this purpose. It is not necessary to have a 
Fig. 64.—Rhubarb growing in coldframe. 
depth of more than 18 inches to 2 feet of manure, unless 
the climate is very severe. In mild sections a foot of hot 
manure will be adequate to force the crop. Pits, caves 
and cellars of various descriptions are used. Small pits 
and cellars are sometimes heated with lamps or stoves. 
Steam or hot water, however, is always preferable, 
though good results may be had with stoves. 
There are many cheaply constructed, commercial 
rhubarb houses. (Fig. 66.) Sometimes these struc- 
tures are several hundred feet long and 15 feet or 
more in width. They may be built as sheds along the 
