HOTBEDS 51 



advisable to dig the pit in tiie fall before the ground is frozen 

 and fill it with leaves or with coarse manure. 



The size of the pit will depend upon the size of the hotbed, 

 and whether it is for home use or for commercial purposes. 

 In either case the size of the pit should be just a trifle larger 

 than the frame, so the frame will fit into it snugly. 



The depth of the pit depends upon several factors: (1) 

 Latitude. The section of the country or the latitude deter- 

 mines the depth to a large degree, because the inside heat of 

 the frame is materially influenced by the external tem- 

 perature. (2) The time of the year. When crops are started 

 late in the season, as for example in March or April, less 

 heat and consequently less depth in the pit is required than 

 if the plants are started in February or earlier. (3) The kind 

 of a crop. Certain plants known as tender or warm-weather 

 plants, such as the tomato, pepper, or egg plant require con- 

 siderably more heat than the more hardy plants as the 

 cabbage or the lettuce. Therefore the pit must of necessity 

 be deeper, to supply the proper amount of heat to grow the 

 warm plants successfully. In the North the customary depth 

 varies from 15 to 36 inches. The depth gradually decreases 

 as one goes south where it ranges from 6 to 12 inches. The 

 heating material which is used and the length of time the 

 hotbed will be needed also influences its depth. 



Hotbed Frame. — Five materials are prominent in the con- 

 struction of the frame: (1) wood, (2) concrete, (3) stone, 

 (4) brick, and (5) cement blocks. Concrete is without a 

 doubt the most durable as well as the neatest, although wood 

 is more generally used because of its cheapness. If wood is 

 used, it is advisable to secure cedar, locust, or cypress, since 

 these woods are the most durable, and will withstand the 

 trying conditions under which the frame is placed. The 

 frame should be made to fit the pit. The length should be 

 determined by the needs of the grower. The usual width is 

 6 feet, because the standard size of the sash is 3 x 6 feet. 

 It is always more convenient to have the width of the 

 frame about one-half inch less than the length of the sash. 

 The upper side of the frame should be 6 or 8 inches higher 

 than the lower side so as to give the proper slope to the frame. 



