78 Gardening Under Glass 



out fresh air, and then wonder why they don't 

 do better. 



When to Give Fresh Air 



In the modern standard construction green- 

 house the control of air is a very simple matter. 

 A twist or two of an easy -turning wheel, and the 

 trick is done — the ventilators being placed where 

 they will not cause direct drafts of air to strike 

 the plants. 



"Giving the plants air" used to be quite a 

 job when you had to climb up and regulate each 

 sash with a strip of iron full of holes to fit over a 

 pin. But modern ventilating apparatus works 

 so easily, and quietly, and perfectly, that you 

 like to work it. The way you can close your 

 house up in a jiffy when a sudden storm comes 

 out of the northwest; and then having turned on 

 the heat, watch the snow begin to pile up and 

 drift outside, but melt and run off the roof of 

 the glass garden — will surely send a thrill of pleas- 

 ure to the heart of any lover of plants. 



There is yet one other thing which is necessary 

 to keep the plants happy. Like everything else, 

 from a puff-ball to a bishop's soul, a plant must 

 express happiness in growth. To keep on grow- 

 ing, it will, from time to time, need more room. 

 More room for its spreading branches; more 



