CULTURAL DIRECTIONS 
355 
without protection in favorable seasons in the Norfolk 
region; they often pass the winter uninjured on Long 
Island, especially if covered 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. Salamander thrives bet- 
ter under adverse soil conditions and in midsummer than 
most other heading varieties. Some of the largest and 
most successful plantations of the North and South are 
in muck soils. Big Boston and Iceberg are commonly 
selected for these lands. 
492. Seed. — Most of the seed used in this country is 
grown in California. Professor Tracy reports that 500 
acres are planted in California every year for lettuce seed, 
from which the annual harvest amounts to 250,000 
pounds. Thirty to 60 plants 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 
