VEGETABLE FORCING 57 



of the season prolonging the use of the houses 

 well into the hot weather, long after such crops 

 as lettuce, cauliflower, and radishes must be 

 abandoned on account of their heat require- 

 ments. For this reason the cucumber becomes 

 a very important member of the group. The 

 tomato is its only rival for greenhouse space at 

 the season. At the extreme Southern limit of 

 the vegetable forcing industry cucumbers are 

 grown as the only greenhouse crop. At the 

 North, however, they are almost universally 

 used after the third crop of lettuce. 



At the season at which cucumbers occupy the 

 greenhouse, following lettuce as they usually do, 

 little expense is required in maintaining the tem- 

 perature. Care is essential, however, to see 

 that the plants never suffer from sudden 

 changes or from cold. Like tomatoes, cucum- 

 bers require higher heat than lettuce. A day 

 temperature from 70 to 75 F. and a night 

 temperature never lower than 60 F. is desir- 

 able. Unless conditions are favorable for the 

 entrance of insects, attention to pollination will 

 be necessary. This can be most economically 

 accomplished by placing a stand of honey bees 

 in the house if it be an extensive one. A small 

 bed can be hand pollinated. In no event should 

 this detail be neglected. Well-grown green- 



