CHAPTER V 

 The Greenhouse Gay 



To Kill Green Fly in Greenhouse 



Q. I have a greenhouse 9 by 5 feet, and I am removing into it 

 about thirty Chrysanthemums Japanese and incurved varieties. I 

 want to fumigate them with the XL ALL vaporising compound, in 

 the liquid (I suppose this is one of the best preparations for green fly, 

 etc. 1) and should be glad to know how much liquid would be 

 required to fumigate them. Would it in any way injure the flowers if 

 they were in bloom when it was done ? Constant Reader, Ulverston. 



A. Yes; if you use XL ALL vaporising compound according to 

 the instructions given with it, all the insect pests will be killed. 

 Place the lamp on the ground near the centre of the house. A 

 dessertspoonful would not be sufficient, but a tablespoonful would. 

 Keep the ventilators closed all night, opening them the following 

 morning. If not successful the first night use the compound again the 

 following night. If the flowers are dry they will not be damaged. 



Fern Fronds Turning White 



Q. I enclose a fern frond. Could you tell me what is the reason 

 for its turning white like that ? I have several varieties of this fern, 

 and they all are attacked by insects. H. T., Macclesjield. 



A. The reason for your fern fronds turning white, as you describe, 

 is that they are covered with the small insect known to gardeners as 

 thrips. The insect is known scientifically as Heliothrips adomdum, 

 and feeds on almost any kind of plants. The insects are usually 

 most prevalent on plants that are growing in a temperature that is 

 too high and ,an atmosphere that is too dry for them, and a bad 

 attack is a serious matter and denotes bad culture. Your best plan 

 is to cut away all the worst of the fronds, and burn them. Then dip 

 the plants in an insecticide, such as Fir tree oil mixture or a nicotine 

 mixture, several days running, and well fumigate the houfe once a 

 fortnight for the next two months. Lower the temperature, keep 

 the house well damped down and the plants well syringed, and you 

 will soon see an improvement. 



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