172 



Commercial Gardening 



are performing the important work of feeding and ripening the fruits. 

 When leaves, therefore, are cut away, or only partially cut away, as shown 

 in the annexed drawings, the wounds caused have first of all to be healed 

 up before the mutilated remains can proceed with their work of absorbing 

 the carbon (which, apart from water, forms the great bulk of the plants 

 and fruits) from the atmosphere. 



The only leaves that should be removed are those that are turning 

 yellow at the base, and those showing the slightest traces of fungoid 



Fig. 495. Common Example of Reckless 

 and Injurious Defoliation 



Fig. 496. Tomato Plant, partially defoliated 

 and injured 



disease, and these should be burned immediately instead of being thrown 

 on the rubbish heap. 



Ventilation. When Tomatoes are grown under glass it is essential 

 to keep the atmosphere pure and fresh. This can only be done by 

 proper ventilation Houses properly built will have plenty of ventilators 

 along the top, near the ridge board, those on one side alternating with 

 those on the other. Ventilators will also be let into the sides; and in 

 large houses there may be a second set about midway between the ridge 

 and gutters. During the summer months all the ventilators may be open 

 to their full extent. In this way there will be a good but not draughty 

 circulation of fresh air, the movement of which carries the pollen from 



