96 DISEASES OF THE SWEET PEA 



This will help to drain off the excess of 

 water likely to be applied by unskilled or 

 inexperienced help. 



Water is not the only important factor 

 in controlling or increasing fungous pests 

 under glass. Temperature also plays an 

 important role. Damping off of green- 

 house sweet peas is best controlled by 

 keeping the greenhouse at a temperature 

 of 50 to 60 degrees F. A temperature of 

 80 to go degrees F. with a high moisture 

 content of the air will cause all young 

 seedlings to damp off, if the fungus is 

 present in the soil. It is doubtful if tem- 

 perature greatly influences the control of 

 collar rot, although a temperature of 90 

 degrees will be more favorable to the fun- 

 gus than a temperature of 50 degrees F. 

 Nevertheless, a low temperature will not 

 considerably check this disease when it 

 once gets a start. In greenhouses where 



