irae Pik FV. 
LET TUCE-* 
LETTUCE is the most popular and the most uniformly 
profitable of all vegetable crops grown under glass in this 
country. It grows rapidly, so that three crops can be 
taken from a house between September and April, and 
the demand for a choice product is always good. Lettuce 
is generally considered to be an easy crop to grow under 
glass, and yet it is a fact that few gardeners are entirely 
successful with the crop, year by year, particularly if the 
heading varieties are grown. It thrives best in late 
winter, but if careful attention is given to watering and 
ventilating, it thrives well in midwinter. Good head let- 
tuces should bring 50 cents or 60 cents a dozen heads at 
wholesale, and they often bring more. The loose types 
generally bring somewhat less. 
Lettuce varies greatly in quality, and this variation is 
due in very great measure to the immediate conditions 
under which it is grown. If the plant is very rank, and 
has dark green, thick leaves, the quality is low. A good 
*As stated in the preface, much of the discussion upon methods of 
forcing of vegetables which is presented in this book is founded upon 
bulletins of the Cornell Experiment Station. Some of these bulletins are 
now out of print, and new notes and experiences are constantly ac- 
cumulating, so that it seems to be necessary to revise the advice and 
to extend it with the observations and experiences of others, and 
thereby to present a consecutive manual. It should be added that 
these same bulletins formed the basis of much of Winkler’s ‘* Vegeta- 
ble Forcing,’ and this fact may account for some similarities of lan- 
guage in the two books. 
(93) 
