In the United States, an 1885 agricultural report listed no fewer than 87 varieties of lettuce. Today, there are four basic types of lettuce: butterhead, iceberg, loose leaf, and romaine. You are likely to find all of these in the produce sections of most supermarkets.
- Butterhead lettuce: This type includes Boston and Bibb lettuces, which are characterized by a loose head and grass-green leaves. Both have a soft “buttery” texture and a sweet, mild flavor. A head of Boston lettuce resembles a flowering rose. Bibb lettuce—also called limestone—forms a smaller, cup-shaped head. Hydroponically grown butterhead lettuce is becoming a more frequent find in supermarkets. The heads have intact roots that are kept submerged in water in a small recess at the bottom of the clear plastic packages. While more expensive, the heads have an extraordinarily long home refrigerator shelf life (a month or even more) as long as the roots are kept wet. So if you like to use just a few lettuce leaves at a time (say, for sandwiches), hydroponic lettuce can be a convenience and sometimes even a bargain.
- Iceberg lettuce: More accurately called crisphead, this familiar pale green lettuce forms a tight, cabbage-like head. Its texture is crisp and its flavor very mild. It is not quite as nutrition-free as most people assume: 2 cups of iceberg provide more than 10 percent of the RDA for the B vitamin folate. There are also no better choices in the lettuce world when you want an extremely crisp lettuce, as for chopped salads, or a nice wedge with blue cheese dressing.
- Loose leaf lettuce: This type of lettuce comprises a number of varieties that don’t form heads, but consist of large, loosely packed leaves joined at a stem. The leaves are either green or shaded to deep red at the edges, and may be ruffled or smooth. Their degree of crispness is midway between romaine and butterhead, their taste is mild and delicate. Red leafand green leaf are popular varieties. Oak leaf, both red and green, forms smaller heads, with flatter leaves shaped like big, floppy oak leaves. For home gardeners, loose leaf lettuce has an advantage over other types: If you pick leaves individually instead of pulling the whole head from the ground, the leaves will continue to replace themselves throughout the season.
- Romaine lettuce: Also called cos, this lettuce has long, deep green leaves that form a loaf-shaped head. Some varieties develop a closed head, others are more open. The main ingredient in Caesar salads, romaine has a crisp texture and a strong, but not bitter, taste.
- Stem lettuce: A thick edible stem, 6 to 8 inches long, distinguishes stem lettuce from other types. It is widely grown in China, and is also known as Chinese lettuce. The only variety available in the United States is called celtuce. Stem lettuce has a mild flavor that is sometimes described as “nutty cucumber.” Stem lettuce is good in salads, but can also be cooked like a vegetable.
See our gallery of 10 Satisfying Main-Dish Salads.