CULTURAL DIRECTIONS 355 



without protection in the Norfolk region ; they often pass 

 the winter uninjured on Long Island, especially if cov- 

 ered with a light mulch. 



491. Soil. Warm, sandy soils when properly fer- 

 tilized are preferable for growing the very early crop ; 

 sandy loams furnish the best conditions for all classes 

 of lettuce. Head lettuce never thrives in close, compact 

 soils. For this reason the large plantings, in the open as 

 well as under glass, are usually found on sandy soils. 

 Grand Rapids can be grown in almost any soil properly 

 enriched with stable manures. Big Boston is the best of 

 the heading class for soils and conditions adverse to the 

 best results. Some of the largest and most successful 

 plantations of the North and South are in muck soils. Big 

 Boston is almost invariably selected for these lands. 



492. Seed. Most of the seed used in this country is 

 grown in California. Professor Tracy reports, in the 

 bulletin previously referred to, that 500 acres are planted 

 in California every year for lettuce seed. The annual 

 harvest in that state amounts to 250,000 pounds of seed. 

 From 30 to 60 plants will produce a pound of seed. 



The greatest care should be exercised in the produc- 

 tion of lettuce seed. Some of the most careful commer- 

 cial growers produce their own seed from specially se- 

 lected plants. In many instances this has been the 

 means of developing strains of superior merit. 



493. Starting early plants. The following methods 

 are employed in starting early plants : 



(1) Sow in the open ground the latter part of Sep- 

 tember or earlier in some sections. Transplant in the 

 cold frames in October, and winter like cabbage plants; 

 set in the field early the next spring. This method was 

 formerly employed almost entirely, but it has not been 

 so common in recent years. 



(2) Sow in the hotbed or the cold frame 5 to 6 weeks 

 before the ground can be worked in the spring, and set in 



