280 Gardening Under Glass 



actually to bring them together may be to the 

 detriment of both. 



Sunshine to the fullest degree is of course req- 

 uisite. Choose a site, therefore, where this is 

 insured and permanently so. The angle of sun- 

 light incidence at noon on the shortest day of 

 the year is 22 degrees; therefore the greenhouse 

 must be kept beyond this angle's distance from 

 anything on its south side. Be careful also to 

 choose a well-drained spot and a comparatively 

 high one, for poor drainage and damp conditions 

 generally are breeders of mildew; and with this 

 handicap in surroundings it is practically impos- 

 sible to maintain the proper atmospheric condi- 

 tions under the glass. 



These conditions being observed the points 

 of the compass may be disregarded generally, 

 though if fruits on trellises are to be grown the 

 trellis should run north and south. This will 

 mean that where it is lengthwise the house itself 

 must run north and south, but where it is cross- 

 wise the house will run east and west, bringing 

 the trellis north and south. 



Its Shape and the Frame 



The type of frame most generally in use to-day 

 is the modified curved eave, whether the struc- 

 ture is an even span or a lean-to. It has very 



