Depending on the variety, leaf lettuce can range in color from medium to dark green and some have red tipped or bronze colored leaves. In the U. S. most lettuce, particularly iceberg type, is grown in California and Arizona. However, Florida is the winter salad bowl capital of the world. Leafy salad greens production begins in Florida in November and continues through early May. Almost all of the nation's endive and escarole comes from Florida.
All salad greens are low in calories.
In general, darker green lettuce leaves are more nutritious than lightly green leaves. Leaf lettuce is more perishable than head lettuce. Choose bunches with crisp evenly color leaves, with no sign of wilting or yellowing at the edges. Leaf lettuce should be washed by running cold water over the leaves or by soaking the loose leaves in the sink with cool water. Leaves should then be dried by blotting with a paper towel or letting drain completely.