LETTUCE. 



225 



large enough to use; such lettuce, however, is not nearly so good 

 as head lettuce where the center is white, crisp and tender. It 

 is a far better plan to thin out the young plants so that they 

 stand three or four inches apart in the rows and in cutting con- 



Figure 118 — Head Lettuce. 



tinue the thinning process so that the later plants will form good 

 heads. Of course, it is necessary to make successive sowings of 

 lettuce in order to have it fit for table use over a long season. 

 Like all leaf crops, lettuce needs plenty of rich, easily avail- 

 able nitrogenous manure and responds very quickly to small ap- 

 plications of nitrate of soda. 



Varieties. — There are many varieties and each year finds 

 many additions to the list of those offered by seedsmen. In 

 the matter of quality, those forming a head like the cabbage 

 have the preference. Varieties that form only a bunch of leaves 

 are largely raised by market gardeners to supply the common 

 demand, since they are more easily grown and are less liable to 

 injury in handling than the heading varieties. Some of the most 

 desirable kinds are as follows: 



White Tennis Bail, or Boston iVIarket. — A very popular 

 market variety adapted for hotbed and early spring use only. 

 It forms a solid head of medium size but quickly goes to seed 

 in warm weather. 



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