62 DREER’S VEGETABLES UNDER GLASS. 
The Boston method of growing lettuce is described in 
Chapter XI, where it is mentioned that the first lettuce crop 
is cut in November. The second crop of lettuce is headed 
about the first of January, and the beds are then made ready 
for cucumbers. 
About December first cucumber seed is sown in a warm 
bed; on heat, as they say. Such a bed is given bottom 
heat from fermenting manure or from steam or hot water 
pipes, usually the latter plan. 
The young cucumber plants are pricked off twice 
(sometimes three times), in order to give them good root 
development; for, as we have elsewhere reminded our 
readers, to transplant a seedling is to discourage its top 
growth and to encourage its root growth. 
The seedling cucumber plants are finally potted in five- 
inch or six inch pots, and by the first of January, under 
proper management, they are well started and vigorous, and 
the pot is full of roots. 
The White Spine cucumber, or one of its improved 
forms, is the variety commonly used at Boston at this time. 
Arlington White Spine is a favorite. The seed is grown in 
the open air. 
It will be remembered that the beds of the great New 
England forcing houses are made upon the ground, and that 
the soil is deep and mellow. For each of the two crops of 
lettuce grown a heavy coat of well-rotted manure is used, so 
that when the time comes for cucumbers the soil is well 
supplied with plant food of just the kind needed by the rank 
feeding roots. 
But this is not enough; for previous to setting the plants 
in the beds (early in January) trenches are dug from end to 
end of the house, about a foot wide and a foot and a-half 
deep. Not more than two or three trenches can be dug in 
an ordinary house, as the vines require a great deal of space 
for their proper development. From a single cucumber row 
