VENTILATION 



107 



Fig. 33. — Shading Cyclamen. Proper shading during the hot Summer months 

 is an important feature of Cyclamen culture. Too much or too dense shade is 

 worse than none at all. Just enough to prevent the plants from wilting is the 

 thing and if, whatever method you use, you can remove it easily, so much the better 



to open or close up at any certain time of the day. It all depends 

 on the weather conditions. 



Special Problems in the Fall 



At no other time of the year do the ventilators play as important 

 a part as during Fall, when you gradually change from Summer to 

 Winter conditions. That is when the eyes of the man in charge 

 of the Rose or Poinsettia house should be open and his hand be 

 on the wheel all day long. Many a dose of mildew on Roses could 

 be avoided if the ventilators were watched more closely and the 

 same with yeUow leaves on the Poinsettias or tender Begonias. 

 Too many growers open their ventilators when the sun warms 

 things up above a certain degree and leave them open until the 

 sun goes down or even long after it has gone down, whereas they 

 should have partly shut them or opened them up more and then 

 shut them again several times during the day. Or, in the case 

 of ventilators on both sides of the roof, the north ones should have 

 been opened and the south ones closed, or vice versa, according to 

 the shifting of the winds. There is no "best way" to have ventilators 

 stationed, and it is impossible to say whether they should open at 

 the top or at the bottom. A good way, however, is to have them 

 on both sides of the ridge so you can open the ones best suited to 



