Lettuce Facts

Lettuce Facts

Lettuce belongs to the genus Lactuca and thistle or daisy family (asteraceae, previously called  Compositae). The garden Lettuce, a type belonging to the species Lactucas scariola, is eaten almost everywhere on earth including Northern Africa, Europe, Asia, and North America. Lettuces add to the color, texture, and flavor of a wide variety of dishes. Cultivated lettuces are commonly added to salads.

The four most common categories of lettuce include: butterhead, looseleaf, romaine, and crisphead.  Butterhead lettuce is round with looser and smoother leaves than those of crisphead lettuce. Crisphead is usually a round-headed lettuce with closely packed leaves. The looseleaf variety has loosely gathered leaves, giving it a rosette appearance. 

A Looseleaf lettuce is easy to cultivate, as it is not entirely harvested. You simply pluck some leaves, and the plant will continue to grow. Romaine lettuce arrived in England in 1500s. Alternatively called cos, romaine lettuces were first cultivated in Italy before  also becoming popular in France and then England.

Lettuces are great sources of vitamins including vitamin A, C, K, thiamine, and riboflavin. However, one of the leading reasons why lettuces are heavily consumed is that they are also very low in calories. Lettuce has a high water content,only a  trace of fat, minimal protein and almost zero carbohydrates, but because it is high in other nutrients, it is among the healthiest low caloric foods available.

Lettuces are raised from seeds that come from all over the world. There are over 50 types of garden lettuces and are not indigenous to all regions of the world. If you want to cultivate lettuce, be sure to choose a variety that will be suitable for your area. Most people find success with the leaf lettuce. Leaf lettuce is easy to grow and is great for hotter regions.

Varieties of lettuce

There are up to six edible varieties of L-sativa lettuce species. These include the crisphead, romaine, butterhead, looseleaf, latin and stem. The first four form the main four categories of lettuce.  Of these six, only crisphead does not occur in both red and green versions. Another point to note is that over the years, varied types of lettuce became very important to different people of the world.

In the U.S, ever since the cultivation of lettuce began  up until the turn of the twentieth century, all varieties were eaten, with many people preferring the butterhead, looseleaf and the American Batavia lettuce. Slowly the Prizehead took the first position at the turn of the century (between 1904 and 1923). Then it was followed by Hanson, Black Seeded Simpson, and Big Boston. By 1923, the New York lettuce had taken the lead, followed closely by the Big Boston, Grand Rapids, Salamander, and Hanson.

In the Mediterranean area: North Africa, Middle East, Italy and Spain, romaine lettuce was, and remains, the favorite variety. It takes many forms and colors.

In northern Europe, the butterhead lettuce and Batavia were very commonly cultivated. Egypt, Middle East and some parts of Asia still cultivate the stem lettuce. As we mentioned above, there are four main categories of lettuce:

1.        Butterhead - This is a form of big head lettuce with large, loose and ruffled leaves that enclose a soft, folded heart. Butterhead is valued in Europe and has a delicious, mild taste and delicately soft-textured leaves. It is high in vitamin A and vitamin K and boasts large amounts of beta-carotene and lutein. Butterhead does well in the warmer days of autumn and the cool days of late spring and early summer.  This lettuce appears in many forms and some of these include:

  • Merveille des Quatre Saisons - Alternatively called French Four Seasons or Continuity, this butterhead, matures in 55 to 60 days. It boasts green, tender leaves with some bronze or red traces.
  • Santoro – It takes the same period of growth as Continuity and boasts bulkier, thicker leaves. Usually perfect in salads, Santoro takes longer to turn bitter than most butterheads. It can be harvested up to three times.
  • Speckles – A crossbreed between Forellenschluss romaine and a green butterhead, the speckles takes 50 to 55 days to mature. It has lovely green leaf surfaces, dotted with some red patches.
  • Drunken Woman Frizzy headed – An open pollinated plant, this butterhead takes 55 days to grow. It has light-green wrinkled leaves with some rose or red colorations if grown in a partially shaded area.
  • Torenia – This one takes 54 days to mature, and it grows some loose, soft-textured heads and pale-green leaves.
  • Blushed butterhead – It forms loose, rose-colored heads of soft leaves. This open pollinated lettuce takes 50 to 55 days.
  • Garden babies – It takes up to 50 days to grow. Garden babies form small domes of squashy leaves.

2.        Romaine – Also called Cos, Romaine lettuce is an open, vertical-headed plant with dark-colored, deeply flavored leaves with brittle midribs. These vegetables grow nicely in warm regions as long as they are properly watered. Just like butterhead lettuces, romaine or cos appears in many forms. Some of them include the following.

  • Breen – Taking 55 days in the garden, Breen is a red romaine lettuce that achieves a height of six to eight inches. It is added to salads.
  • Flashy Trout Back – This is an Austrian heirloom cos that takes 55 days to grow. Its other name is the Forrellenschluss romaine.  Boasting strikingly gorgeous green leaves, this vegetable looks much like the form of a butterhead called speckles. It is very tender for a romaine lettuce and is great for salads.
  • Jericho - This vegetable has dark-green leaves that remain sweet all through the summer season. It takes 57 days to mature.

3.        Crisphead - Also called iceberg lettuce, the crisphead lettuce is heavily cultivated and consumed in the U.S.  This type of lettuce has an even higher water content than other lettuce; it is also lower in nutrients. Before 1920s, the term crisphead was being used to refer to this form of lettuce. But after the crop began to be shipped across the United States, the term iceberg was used. Heads of lettuce were covered with crushed ice before transit, giving them the appearance of an iceberg. The name iceberg was invented by the people who could shout it loudly whenever they heard the train pulling into their stations. This sort of lettuce rolls its leaves into heads by the time it matures. It looks a lot like cabbage.  Crispeads/icebergs are very disease-resistant and can tolerate a lot of summer heat.  Main types include:

  • Great Lakes – This is a standard lettuce that holds very well in warm weather.
  • Red Iceburg – Taking 50 days to mature, the red iceberg is of a medium size. It has tender hearts, and its leaves’ perimeters are light brown.
  • Summertime – This lettuce takes 48 days to mature to a medium size vegetable with green heads and dark, ruffled leaves.
  • Ithaca – This form of crisphead tolerates a lot of summer heat. It also does not become bitter quickly.

4.        Looseleaf – This very colorful plant also grows very quickly. Forming open heads, looseleaf lettuce leaves can be harvested gradually or all at once. In just five weeks, you can have some ready baby leaves to pluck. Main types include the following:

  • Red Oak Leaf   - This type takes 50 to 55 days to mature. Compared to other lettuce species, Red Oak Leaf bolts slowly, stays tender longer and keeps its good flavor for a longer time. This can further be sub-divided into Red Fire, with red-edged ruffles; Red Sails, the slowest to bolt and Ruby, the darkest red of all Red Oak leaf lettuces.
  • Green Oak Leaf – It also takes 50-55 days to mature. Green Oak leaf is slower to bolt, stays tender for longer and takes longer to taste bitter. It is further sub-divided into black-seeded Simpson, the earliest to mature; Oak Leaf, which withstands summer heat and tipburn, and Grand Rapids, a frilly-edged lettuce.
  • Red Salad Bowl - Takes 50 days to grow and shows promising resistance to frost.  This lettuce boasts loose, open heads of dark-red, frilly leaves. It is best sowed in early spring.
  • Blushed Butter Oak – This one takes 55 days to mature. A loose, open head lettuce, the Blushed Butter Oak has leaves that look like oak tree leaves.
  • Red Sails – This one shows slow-bolting signs during the 52 days of growth. Also resistant to tipburn, its green leaves have a rouge overlay. Until it grows a flower stalk, it stays sweet.

Others

Celtuse – A stem lettuce that originates from southern China. It arrived in the western countries in 1890s and was called the asparagus lettuce. In Chinese, it is called Wo Sun or Chinese lettuce. It is the same thing as celery lettuce or stem lettuce. Its thick and long stalks are similar to those of celery, while the leaves are like of those of typical lettuce plants. Celtuse has a mild, delicate flavor just like that of cooked cucumber or asparagus. As a result, celtuse is used to flavor many Chinese dishes including poultry, meat and fish. In place of spinach, you can use a Chinese lettuce. Compared to all lettuce forms we have discussed above, this one takes the longest to mature—90 days.