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. 



