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First of all “Lettuce” is not a specific type of Green or type of Vegetable. Instead, Lettuce is more of a “catch-all” name, like Grains, which is technically applicable to a number of related plants with edible leaves in the genus Lactuca. In practice, any other types of Leafy Greens which are used and eaten in a similar manner as Lettuces, are commonly called Culinary Lettuces.

The Lettuces in the genus Lactuca, true Lettuces, are Annual (or Perennial) Herbs with crisp water-filled leaves in the Asteraceae family which also includes: Artichokes, Sunflowers, Dandelions, Daisys, Marigolds, and Chrysanthemums.

Lettuce Stem

Lettuce has a shortened fleshy stem 10 to 15 cm tall. The stem elongates and

branches in a paniculate manner during the reproductive phase. Each branch

terminates in a homogamous capitulum with ligulate, hermaphrodite pale yellow leaves.

Lettuce Leaves

It produces a rosette of smooth, radical, spirally arranged leaves.

We believe Lettuce originated from Asia, where it was grown for centuries and its early forms were used in Egypt around 4500 BC. The Romans grew types of lettuce resembling the present romaine cultivars as early as the beginning of the Christian era. The crop was also used in China by the 7th century A.D.

Lettuce is now one of the world’s most important salad crops and is grown Worldwide.


Lettuce is an early annual crop that grows best in cool weather and with ample water.


Lettuce is available all year long.


Lettuce is a delicate vegetable and great care should be taken when selecting and storing. Most Lettuce is showcased on ice or in refrigeration. When selecting your leaves, be sure that they are fresh and crisp, with no signs of wilting, slim, or dark spots or edges. Remember when selecting your Lettuce that the darker outer leaves are the most nutritious.


Lettuce tends to keep well in plastic bags in the crisper section of the refrigerator. Iceberg Lettuce keeps the best, lasting around two weeks, while Romaine Lettuce, ten days, and Butter Lettuce and Endives lasts approximately four days. The very delicate greens don’t last very long, so it’s best to buy only as much as you need at one time and use immediately.

Salad greens should not be stored near fruits that produce ethylene gases (like apples) as this will increase brown spots on the lettuce leaves and increase spoilage. Greens that are bought in bunches should be checked for insects. Those leaves that have roots should be placed in a glass of water with a bag over the leaves and then placed in the refrigerator.

Culinary Uses

Lettuce is generally eaten fresh in Salads, although there are numerous dishes in which the leaves are Stuffed, Braised, Grilled, or Pureed.

Lettuce leaves can also generally be found in Soups, Sandwiches and Wraps, while the stems are eaten both Raw and cooked.

Portion Size

Allow 1-2 oz of Lettuce per person.

Nutritional Value USDA
Amount Per 100g
Calories 15
%Daily Value*
Total Fat 0g
Saturated Fat 0g
Polyunsaturated Fat 0g
Monounsaturated Fat 0g
Cholesterol 0mg
Sodium 28mg
Potassium 194mg
Total Carbohydrate 2g
Dietary Fiber 1g
Sugars 0g
Protein 1g
* Percent Daily Values are based on a 2,000 calorie diet. Your Daily Values may be higher or lower depending on your calorie needs.

Lettuce is a good source of vitamin A and potassium, as well as a minor source for several other vitamins and nutrients. Despite its beneficial properties, Lettuce when contaminated is often a source of bacterial, viral and parasitic outbreaks in humans, including E. Coli and Salmonella. In addition to its main use as a leafy green, it has also gathered religious and medicinal significance over centuries of human consumption.

Gluten Free


Low Fat


Low Calorie