268 FRUIT CULTURE UNDER GLASS. 



plants under careful treatment often go on bearing 

 until the house is needed for another winter set of 

 plants. 



INSECTS. 



Thrips and red-spider are very apt to be troublesome 

 on winter cucumbers, and their first appearance must 

 be the signal for their destruction. See directions for 

 destroying these insects at close of chapter on Melons. 



DISEASES. 



The cucumber-plant is subject to mildew when grown 

 in too low a temperature, and kept too wet or too dry 

 at the root. Whenever it appears, dust the affected 

 parts with sulphur. Keep the bottom and top heat 

 up to what I have recommended, and give air freely ; 

 under such conditions it will disappear. Gumming 

 and canker, with which they are sometimes affected, 

 is caused by the want of sufficient bottom-heat and 

 over-watering. Whenever it appears on the fruit or 

 plants, raise the bottom -heat, and apply less water 

 both at the root and in the air, and dust the affected 

 parts with newly-slaked lime. In such houses as I 

 have recommended, and with attention to the heat 

 and watering, neither of these diseases is likely to 

 attack the plants. Deformed fruit are often seen on 

 cucumbers. They are the result of general debility, 

 and a sure sign that the plants are not sufficiently 

 nourished, and that the temperature has been too low. 

 To prevent malformed fruits, do not crop too heavily, 

 top-dress the soil with rotten dung, and keep the 

 temperature in the soil and air as has been directed. 



