Forcing-House Miscellanies. 387 



The average gas consumption for the few days of the test, as 

 charged by the gas company, was 650 cubic feet per day. At the 

 price we paid for gas, the expense of running the heater was pro- 

 hibitive, and it was given up with much reluctance. 



LETTUCE. 



Lettuce is the most popular and the most uniformily 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 j)roduct 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 suc- 

 cessful with the crop, year by year, particularly if the heading 

 varieties are grown. 



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 lettuce plant is yellowish green in color 

 upon delivery, and the leaves are thin and brittle. The product 

 should be wholly free from lice, or green-fly, and the tips of the 

 leaves should show no tendency to wither or to turn browm. If 

 heading lettuce is grown, the leaves should roll inward like cabbage 

 leaves, the heads should be compact and nearly globular and yellow- 

 ish white toward the core. 



It is not my purpose to enter into a full account of lettuce forcing 

 at this time ; I desire only to suggest a few of the most important 

 points in the cultivation of the crop, as they have presented them- 

 selves to me during the past few years. 



In the first place, lettuce must have a low temperature. The 

 night temperature should not rise above 45°, while it may go as low 

 as 40° or even lower. The day temperature, in the shade, should 

 be 55° to 65°. Lettuce which is kept too warm grows too tall, and 

 the leaves are thin and flabby ; and there is generally more danger 

 of injury from aphis, rot and leaf-bum. 



Whilst a lettuce house must have an abundance of light, the 

 plants do not suffer if they are some distance from the glass and even 

 if they receive little direct sunlight. The house should have an 

 exposure toward the sun and the framework ought to be as light 

 a& possible, if the best results are to be obtained ; but diffused light 



