LEAVES AND STEMS WE EAT 1 23 



As to cultivation, three classes of lettuces have 

 been developed: (i) Quick-growing spring varie- 

 ties; (2) large, heat-resisting summer varieties; 

 (3) hardy winter varieties. 



The Boston head lettuce, with its crumpled, 

 plain-marginned leaves, tender and rich in flavor, 

 from the green outside to the white centre, is the 

 favorite in this country. It is grown the year 

 round in the open, in hotbeds, in cold frames, for 

 home use and for city markets. 



The English people, at home and in Canada, 

 are devoted to the Cos lettuces, with the long 

 head of spoon-shaped leaves, tender and rich in 

 flavor, with midribs thick and white, almost like 

 those of Swiss chard. These leaves are eaten like 

 celery, dipped in salt, as well as in salads. Ameri- 

 cans are learning to grow these excellent varieties. 



The cool, damp climate of England is admir- 

 ably adapted to lettuce culture. Many of the 

 hundred cultivated varieties have originated in 

 English experimental grounds. Loose, rich soil 

 and good culture keep the plants growing rapidly, 

 which is the main aim in the production of any 

 leaf crop. 



Since growth takes place in daylight, and the 

 plants rest by night, experiments to test the 

 effects of artificial light have been made. Lettuce 



