328 GARDEN GUIDE 



Standard size sash covers a space 3 by 6 ft. , and the frames to sup- 

 port it are made to correspond. In building of wood it is better to use 

 2-in. planks, although inch boards are often employed. In building a 

 wooden frame, after ascertaining the correct size to fit the particular 

 sash you are buying, put in posts of 3 by 4 in. stuff with the inside corner 

 planed down for an inch or so, to avoid a sharp edge. There should 

 be a drop of about from 3 to 4 in. from the back to the front. If you 

 can get boards or planks 6 and 9 in. wide, and 6 or 12 ft. in length, 

 practically no cutting will have to be done in building the frame. Let 

 the sides come down well below the ground as the soil inside should be 

 a few inches below the general ground level. After it is finished, a layer 

 of gravel or roofing slate on the outside, or banking up with soil, nearly 

 to the top, will greatly increase its efficiency in keeping out cold. 

 Concrete frames should be made 4 to 6 in. thick and sunk well below 

 the ground level so that the frost cannot get under the mason work. 



At least part of your sash should be of the double'glazed type. Two 

 layers of glass instead of one are used, with the result that the thin 

 air space left between them forms a 

 cushion of dead air which is as effective as 

 a blanket of wool or canvas in keeping 

 out the cold, while it admits the light 

 and sunshine as readily as a single layer 

 of glass. With a good tight frame and 

 double glass sash, crops may be grown 

 well into the Winter, and started 

 very early in the Spring, without any 

 other protection. ^'"^^ '^""''^^ ^"^"^^ 



With single glass sash, wooden shutters or burlap mats are used as 

 an extra covering in cold weather. If these are employed in addition to 

 double glass sash, half hardy crops, such as Lettuce, can be carried 

 through very severe weather without any artificial heat at all, and the 

 frames will be ready for use in the Spring as early as they may be 

 wanted, without having to wait for them to thaw out. 



Hotbeds are made one to two feet deeper than for coldframes, to 

 allow for the layer of manure put in to furnish the heat. 



Location 



Generally it is best to locate with southern exposure and with a 

 protection of trees or fence at north (see p. 330) . Three feet should be 

 allowed back of frame to the fence to allow for working facilities. Do 

 not put the frame where the Spring rains may drain into it. Good 

 drainage is especially important in Winter as well as in Spring. 



