because it is
hrfj
Lettuce and tomatoes
Citrus, lettuce (capital of the world), dates and cotton.
AZ if i kno
Lettuce (Lactuca sativa) is grown as a leafy vegetable. It was first cultivated by the ancient Egyptians. Lettuce grows best in full sun in loose, nitrogen-rich soils with a pH between 6.0 and 6.8. Partial shade is important when growing lettuce during the warm season -- it keeps the lettuce from bolting (producing flowers and seeds).
Iceberg lettuce actually doesn't have much nutrition at all...it is mostly water. Greener lettuces, like romane lettuce, are packed with more vitamins and other important nutrients.
The possessive form for the singular noun lettuce is lettuce's.
"As a rule of thumb, the outer leaves as well as lettuce varieties that are dark green and reddish in color are the most nutritious. But even popular, but pale, iceberg lettuce provides water, fiber, folate, and small amounts of other important vitamins and minerals like zinc and potassium." -http://www.bcm.edu/cnrc/consumer/archives/lettuce.htm
romaine lettuce is different because it is much fresher than reg lettuce.
The noun lettuce has varied usage in the plural. Traditionally the usage is "three heads of lettuce", but the alternative "three lettuces" has become very common during the last century. The collective noun is always "I like lettuce" or "this farmer grows lettuce".
From Overgaard, Az. to Phoenix, Az. 138 miles.