Ventilating 



75 



Fig. 23. Ventilating the hotbed. 



Ventilation is important, (1) to dry the air, (2) 

 to aid in controlling the temperature. Plants which are 

 kept close and wet tend to grow too tall and soft, and 

 to lack in stockiness. On pleasant and sunny days, 

 ventilation should be given by 

 raising the sash, resting it on 

 a notched block, (Fig. 23), 

 or by sliding down the sash. 

 The general tendency with be- 

 ginners is to ventilate too little 

 rather than too much. One is 

 likely to judge the temperature 

 by the wind and air about his 

 face and ears, whereas the hot- 

 bed, being on the surface of 

 the ground, is considerably 



warmer and more protected. Whenever the air in the 

 bed is so moist that drops of water collect on the panes, 

 ventilation should be given if the temperature will per- 

 mit. In fact, it is the aim of good gardeners not to 

 have the atmosphere very moist when the temperature 

 is low and ventilation cannot be given. As the plants 

 grow, more and more ventilation should be given until 

 finally in sunny days the sash can be stripped from the 

 frames. In this way the plants become accustomed to 

 the lower temperature and to normal conditions of the 

 atmosphere ; they become hardened. Careful atten- 

 tion to ventilation is one of the important means of 

 making plants stocky. 



Hardening -off is also promoted by giving the plants 

 plenty of room. As soon as they begin to crowd, some 



