GLASS STRUCTURES. 



69 



after the middle of April the sun is pretty high and the bed well 

 warmed, the plants will continue to flourish. 



Hotbeds require more water than cold frames and more care 

 in the matter of ventilation. They should not be started until 

 a short time before one is ready to use them. If seedlings are tc 

 be raised in them to be later on transplanted, start only enough 

 sashes to grow the seedlings and do not start other hotbeds 

 until the seedlings are big enough to be removed into them. 



For the ordinary farm garden four or five hotbed sashes are 

 a great plenty and no more should be started than can be prop- 



Figure 26. — Fire liotbed. 



erly attended to. These should be started about the first oi 

 March. This number will be found sufficient for all the early 

 radishes, onions, lettuce, cress and other greens for the table in 

 early spring, and for raising tomatoes, cabbage and other vege- 

 table plants to be set out later in the open ground. 



Shutters and mats are used for covering the sash of hot- 

 beds and cold frames at night to prevent too rapid radiation of 

 the heat. 



Fire Hotbeds. — Horse manure will undoubtedly continue to 



