CHAPTER IX. 

 HOT-BEDS AND COLD FRAMES. 



Efforts for the multiplication of many plants by seeds or cuttings 

 are promoted by arrangements for regulation of temperatures and of 

 moisture both of soil and air. This regulation is also essential to the 

 success of buds and grafts of tender plants especially when working 

 in soft tissues, as suggested on page 65. 



It is obvious that in California, where the temperature never falls 

 as low as in lands with wintry climates, the arrangements for securing 

 artificial heat, even for the growing of the tenderest plants, are very 

 simple and consist, for the most part, in concentrating and storing 

 winter sun-heat and preventing the intrusion of night temperatures. 

 Even where artificial heat has to be actually produced, by circulation 

 of hot air, hot water or steam, or by the rising of heat from fermenta- 

 tion of manure, but a few degrees of elevation of temperature are 

 required and arrangements altogether inadequate in wintry climates 

 are quite sufficient in California, in all but the high mountain districts. 

 For these reasons in iall amateur operations very simple, home-made, 

 appliances are perfectly adequate. 



HOT-BEDS. 



Hot-beds used in California are exactly similar to those used in 

 colder climates, but they need less protection from outside tempera- 

 tures such as is obtained by banking with manure and covering with 

 mats, etc. They also need less active heat, such as is produced by 

 partly spent manure or by using a smaller mass of fermenting material 

 and they require, perhaps, greater watchfulness against over-heating 

 and freer use of ventilating arrangements for admitting outside air. 

 They also require attention to shading for even the California mid- 

 winter sun is sometimes very fervid. Thus, though the construction of 

 hot-beds here is similar to the traditional structures of colder climates, 

 the use of them has to be guided by local experience and observation. 



The construction of a hot-bed is indicated in Fig. 1. It is made of 

 two-inch planks, spiked or bolted together, though for most uses 

 one-inch redwood boards will serve as well as planks. It is in the 

 form of a rectangular box, generally 6 ft. wide, because that distance 

 is readily reached across from the sides, and as long as desired. 

 The box should be so made that when the bottom is level, the sash 

 will slope 1 in. to the foot, which will make it 6 in. higher on one side 

 than on the other. This slope permits the sun's rays to enter more 

 freely and allows water to run off quickly. The bed should be located 



