CONSTRUCTION OF HOTBEDS 
113 
frames has a tendency to become very dry. To prevent 
this, pans of water should be kept in the frames. Sheds 
may be built at the furnace end of the frames, to provide 
comfortable quarters for the work of seed sowing and 
transplanting. 
162. Heating with steam and hot water. — A frame 
piped and heated by steam is shown in Figure 21. Hot 
water may be used in the same way. When heated by 
either method, mats may be dispensed with. The prin- 
ciples of steam or hot water heating must be observed 
to secure satisfactory results. These systems of heating 
are becoming more popular every year. Drain or sewer 
tile may also be laid in the soil of the frames, steam being 
conducted through them under some pressure. 
163. The uses of hotbeds. — Hotbeds are used for start- 
ing early vegetable plants. The seedlings are started in 
the hotbeds and transplanted into other hotbeds, cold 
frames or the field. Hotbeds are also used in forcing 
some crops to maturity. The most popular vegetables 
for hotbed forcing are radishes and lettuce. Spring and 
summer crops are frequently matured in hotbeds, being 
started over the fermenting manure, or over manure 
whose heating qualities have been exhausted. Among 
the crops grown in this manner are cucumber, musk- 
melon, eggplant, squash, tomato, cauliflower, kale, spin- 
ach, radish and lettuce. 
