Romaine lettuce The World's Healthiest Foords are health-promoting foods that can change your life. Watch for the launch of our new WHFoods 7-Day Meal Plan on January 23rd! The George Mateljan Foundation is a not-for-profit foundation with no commercial interests or advertising. Our mission is to help you eat and cook the healthiest way for optimal health. Romaine lettuce Not all lettuce is created equal, but if you start your meal with a salad made of romaine lettuce you will be sure to add not only a variety of textures and flavors to your meal but an enormous amount of nutritional value. Most of the domestic U.S. harvest of romaine lettuce and other salad greens comes from California and is available throughout the year. Lettuce is synonymous with salads as they are predominantly made from crispy green lettuce leaves. Most varieties of lettuce exude small amounts of a white, milky liquid when their leaves are broken. This "milk" gives lettuce its slightly bitter flavor and its scientific name, Lactuca sativa derived from the Latin word for milk.

Romaine Lettuce, raw pantothenic acid 3% This chart graphically details the %DV that a serving of Romaine lettuce provides for each of the nutrients of which it is a good, very good, or excellent source according to our Food Rating System. Additional information about the amount of these nutrients provided by Romaine lettuce can be found in the Food Rating System Chart . A link that takes you to the In-Depth Nutritional Profile for Romaine lettuce, featuring information over 80 nutrients, can be found under the Food Rating System Chart. References Health Benefits Want to maximize the health benefits of your salads? Start with romaine lettuce for a salad guaranteed to be packed with nutrients. The vitamins, minerals, phytonutrients and fiber found in romaine lettuce are especially good for the prevention or alleviation of many common health complaints. Due to its extremely low calorie content and high water volume, romaine lettuce—while often overlooked in the nutrition world—is actually a very nutritious food.

Based on its nutrient richness, our food ranking system qualified it as an excellent source of vitamin A (notably through its concentration of the pro-vitamin A carotenoid, beta-carotene), vitamin K, folate, and molybdenum. Romaine lettuce also emerged from our ranking system as a very good source of dietary fiber, four minerals (manganese, potassium, copper, and iron), and three vitamins (biotin, vitamin B1, and vitamin C). Salad Days Keep Your Heart Young Romaine's vitamin C and beta-carotene content make it a heart-healthy green. Vitamin C and beta-carotene work together to prevent the oxidation of cholesterol. When cholesterol becomes oxidized, it becomes sticky and starts to build up in the artery walls forming plaques. If these plaques become too large, they can block off blood flow or break, causing a clot that triggers a heart attack or stroke. The fiber in Romaine lettuce adds another plus in its column of heart-healthy effects. In the colon, fiber binds to bile salts and removes them from the body. This forces the body to make more bile, which is helpful because it must break down cholesterol to do so.

This is just one way in which fiber is able to lower high cholesterol levels. Equally beneficial to heart health is Romaine's folic acid content. This B vitamin is needed by the body to convert a damaging chemical called homocysteine into other, benign substances. If not converted, homocysteine can directly damage blood vessels, thus greatly increasing the risk of heart attack and stroke. In addition, romaine lettuce is a very good source of potassium , which has been shown in numerous studies to be useful in lowering high blood pressure, another risk factor for heart disease. With its folic acid, vitamin C, beta-carotene, potassium, and fiber content, romaine lettuce can significantly contribute to a heart-healthy diet. Description The words lettuce and salad are practically interchangeable since most salads are made predominantly with the green crispy leaves of lettuce. Most varieties of lettuce exude small amounts of a white, milky liquid when their leaves are broken. This "milk" gives lettuce its slightly bitter flavor and its scientific name, Lactuca sativa since Lactuca is derived from the Latin word for milk.

Lettuce can be classified into various categories with the most common being: Romaine: Also known as Cos, this variety of head forming lettuce has deep green, long leaves with a crisp texture and deep taste. Crisphead: With green leaves on the outside and whitish ones on the inside, this variety of head lettuce has a crisp texture and a watery, mild taste. The best known variety of crisphead lettuce is iceberg. Butterhead: These types of lettuce feature tender large leaves that form a loosely arranged head that is easily separated from the stem, a sweet flavor and a soft texture. The best known varieties of Butterhead lettuce include Boston and Bibb. Leaf: Featuring broad, curly leaf varieties that are green and/or red, the leaf lettuces offer a delicate taste and a mildly crispy texture. Best known varieties of leaf lettuce include green leaf and red leaf. While vegetables such as arugula, watercress and mizuna are not technically lettuce, these greens are often used interchangeably with lettuces in salads. History Native to the eastern Mediterranean region and western Asia, lettuce has a long and distinguished history.

With depictions appearing in ancient Egyptian tombs, the cultivation of lettuce is thought to date back to at least 4500 BC. The ancient Greeks and Romans held lettuce in high regard both as a food and for its therapeutic medicinal properties. In China, where lettuce has been growing since the 5th century, lettuce represents good luck. It is served on birthdays, New Year's Day and other special occasions. Christopher Columbus introduced varieties of lettuce to North America during his second voyage in 1493. Lettuce was first planted in California, the lettuce capital of the United States, by the Spanish missionaries in the 17th century. Its popularity across the US did not become widespread until centuries later with the development of refrigeration and railway transportation. How to Select and Store Regardless of the type, all lettuces should feature crisp looking, unwilted leaves that are free of dark or slimy spots. In addition, the leaves' edges should be free of brown or yellow discoloration. Lettuces such as Romaine and Boston should have compact heads and stem ends that are not too brown. At WHFoods, we encourage the purchase of certified organically grown foods, and lettuce is no exception.

Repeated research studies on organic foods as a group show that your likelihood of exposure to contaminants such as pesticides and heavy metals can be greatly reduced through the purchased of certified organic foods, including lettuce. In many cases, you may be able to find a local organic grower who sells lettuce but has not applied for formal organic certification either through the U.S. Department of Agriculture (USDA) or through a state agency. (Examples of states offering state-certified organic foods include California, New York, Oregon, Vermont, and Washington.) However, if you are shopping in a large supermarket, your most reliable source of organically grown lettuce is very likely to be lettuce that displays the USDA organic logo. Since different types of lettuce have different qualities, different methods should be used when storing. Romaine and leaf lettuce should be washed and dried before storing in the refrigerator to remove their excess moisture, while Boston lettuce need not be washed before storing. A salad spinner can be very helpful in the drying of lettuce (and other salad ingredients as well). These lettuces should be either stored in a plastic bag or wrapped in a damp cloth and stored in the refrigerator crisper.

To store arugula, watercress and other types of salad greens that are sold with their roots attached, wrap the roots in a damp paper towel and place the entire greens in a plastic bag. Romaine lettuce will keep for five to seven days, Boston and leaf lettuce for two to three days, while fragile greens such as arugula and watercress ideally should be prepared the day of purchase. All types of lettuce should be stored away from ethylene-producing fruits, such as apples, bananas and pears, since they will cause the lettuce leaves to brown. Here is some background on why we recommend refrigerating lettuce. Whenever food is stored, four basic factors affect its nutrient composition: exposure to air, exposure to light, exposure to heat, and length of time in storage. Vitamin C, vitamin B6, and carotenoids are good examples of nutrients highly susceptible to heat, and for this reason, their loss from food is very likely to be slowed down through refrigeration. Tips for Preparing and Cooking Tips for Preparing Romaine Lettuce To clean lettuce, first remove the outer leaves and with one slice cut off the tips of the lettuce since they tend to be bitter.

Chop the remaining lettuce to the desired size and discard the bottom root portion. Rinse and pat dry or use a salad spinner if you have one available to remove the excess water. Wash greens such as arugula and watercress like you would spinach. Trim their roots and separate the leaves, placing them in a large bowl of tepid water and swishing them around with your hands. This will allow any sand to become dislodged. Remove the leaves from the water, empty the bowl, refill with clean water and repeat this process until no dirt remains in the water (usually two or three times will do the trick). Make sure your leaves are spun or patted dry before adding dressing so as not to dilute flavor. How to Enjoy Thurinus Thurinus Email Dark red romaine for full size. Attractive red romaine with great contrast between dark red and lighter green at the base of the leaf. Similar color compared to Red Cash, which it replaced. Uniform plants are well-suited for spring, summer, and fall. Utility Patent granted.

High resistance to downy mildew races 1-28, 30, 31 and Nasonovia ribisnigri aphid; and intermediate resistance to lettuce mosaic virus. MT0-30. Also available with NOP-compliant pelleting. Avg. 19,400 seeds/oz. Packet: 500 seeds. More Growing Information CULTURE: Lettuce is hardy and can be planted as early as the soil can be worked. It is a cool weather crop and grows best at temperatures of 60-65°F (16-18°C). Careful variety selection is important for hot weather plantings. Sow every 3 weeks for a continuous supply of fresh lettuce. THERMAL DORMANCY: Lettuce seed can enter thermal dormancy when exposed to high temperatures. Optimum germination results at soil temperatures of 60-68°F (16-20°C). The priming process in pelleted lettuce seeds broadens the temperature range in which the seeds will germinate, overcoming some of their thermal dormancy.

TRANSPLANTING: Sow in flats, 4 seeds/in., or in 3/4" plug trays, barely covering seeds with fine vermiculite, 3-4 weeks before transplanting outdoors. Shade the flats on sunny, warm days if necessary to keep the soil surface cool, below 75°F (24°C), until germination. If sowing into flats, transplant 1-2" apart into flats, pots, or cell-type containers about 2 weeks later. Harden seedlings by reducing water and temperature for 2-3 days before planting outdoors. Properly hardened transplants can survive temperatures as low as 20°F (-6°C). Transplant iceberg and romaine lettuce 10-12" apart, in rows 18" apart. Other types 8-10" apart in rows 12-18" apart for full-size heads or 6" apart for mini heads. DIRECT SEEDING: Seeds germinate even at low, 40°F (4°C), soil temperature, but poorly above 75°F (24°C) depending on the variety and seed lot.

Sow seeds 1" apart, rows 12-18" apart. Cover seed lightly, about 1/8", and firm soil gently. Thin iceberg and romaine lettuce to one plant every 10-12", other types 8-10" for full-size heads or 6" for mini heads. Dry soil must be watered to ensure coolness and moisture, and for uniform germination. SALAD MIX/BABY LEAF: Sow in a 2-4" wide band, about 60 seeds/ft. MT0 SEEDS: A variety's description followed by MT0-30 indicates that the seed offered for sale has been tested for the presence of Lettuce Mosaic Virus and that no LMV was found in a sample of at least 30,000 seeds. NOTE: A disease-free test result does not guarantee a seed lot to be disease-free, only that in the sample tested, the pathogen was not found. DAYS TO MATURITY: For full-size heads in mild temperatures from direct seeding; subtract 10-14 days if transplanting.

NOTE: Maturity can be 3 or more weeks later in cool weather, and up to 1 week earlier in hot weather. AVG. DIRECT SEEDING RATE: For full-size heads (precision seeded): 1,000 seeds/220', 1 oz./5,300', 5 1/2 oz./acre 2 1/2" apart in rows 18" apart. For baby leaf: 1,000 seeds/16', 1 oz./400', 1 lb./6,400' at 60 seeds/ft. TRANSPLANTS: Avg. 20,000 plants/oz. SEED SPECS: SEEDS/OZ.: Avg. 17,800. PACKET: 500 seeds, unless otherwise indicated. Butterhead Lettuce (Boston) Butterhead Lettuce (Boston) Annual Butterhead Lettuce (Boston) Generally grown to full-size heads, butterhead lettuce receives its name from the sweet buttery flavor and delicate texture of the large, ruffled outer leaves. Cutting into the lettuce reveals a soft, folded, and blanched heart.

Also known as Boston lettuce, this is the sort of lettuce most prized in Europe, where most of our butterhead varieties were bred. More Lettuce Lettuce Lettuce and chicory output in 2005 Lettuce (butterhead) Nutritional value per 100 g (3.5 oz) Energy 10 kcal 60 kJ Carbohydrates Vitamin A equiv. 166 μg 18% Folate (Vit. B9) 73 μg 18% Percentages are relative to US recommendations for adults. Source: USDA Nutrient database The Lettuce (Lactuca sativa) is a temperate annual or biennial plant of the daisy family Asteraceae. It is most often grown as a leaf vegetable. In many countries, it is typically eaten cold and raw, in salads, hamburgers, tacos, and many other dishes. In some places, including China , lettuce is typically eaten cooked and use of the stem is as important as use of the leaf. Both the English name and the Latin name of the genus are ultimately derived from lac, the Latin word for “ milk ”, referring to the plant’s milky juice.

Mild in flavour, it has been described over the centuries as a cooling counterbalance to other ingredients in a salad. In his humorous essay 100 Things I Hate, filmmaker John Waters refers to iceberg lettuce as "the polyester of greens". Description The lettuce plant has a short stem initially (a rosette growth habit), but when it blooms the stem lengthens and branches, and it produces many flower heads that look like those of dandelions , but smaller. This is called bolting. When grown to eat, lettuce is harvested before it bolts. Lettuce is used as a food plant by the larvae of some Lepidoptera. The largest lettuce head, of the Salad Bowl cultivar, weighed 11 kg (25 lb) grown by Colin Bowcock of Willaston, England , in 1974 . Cultivation Lettuce is grown commercially worldwide. History The lettuce that we see today actually started out as a weed around the Mediterranean basin. Served in dishes for over 4500 years, lettuce has certainly made its mark in history- as seen from tomb paintings in Egypt to the depiction of many different varieties in ancient Greek relics. Christopher Columbus introduced lettuce to the new world.

Cultivars There are six commonly recognised Cultivar Groups of lettuce which are ordered here by head formation and leaf structure; there are hundreds of cultivars of lettuce selected for leaf shape and colour, as well as extended field and shelf life, within each of these Cultivar Groups: Butterhead, also called Boston or Bibb, forms loose heads; it has a buttery texture. Butterhead cultivars are most popular in Europe. Chinese lettuce types generally have long, sword-shaped, non-head-forming leaves, with a bitter and robust flavour unlike Western types, appropriate for use in stir-fried dishes and stews. Chinese lettuce cultivars are divided into “stem-use” types (called celtuce in English), and “leaf-use” types such as youmaicai ( Chinese : 油麦菜; pinyin : yóumàicài) or shengcai (生菜). Crisphead, also called Iceberg, which form tight, dense heads that resemble cabbage . They are generally the mildest of the lettuces, valued more for their crunchy texture than for flavour. Cultivars of iceberg lettuce are the most familiar lettuces in the USA .

The name Iceberg comes from the way the lettuce was transported in the US starting in the 1920s on train-wagons covered in crushed ice, making them look like icebergs. Looseleaf, with tender, delicate, and mildly flavoured leaves. This group comprises oak leaf and lollo rosso lettuces. Romaine, also called Cos, grows in a long head of sturdy leaves with a firm rib down the centre. Unlike most lettuces, it is tolerant of heat. Summer Crisp, also called Batavian, which form moderately dense heads with a crunchy texture; this type is intermediate between iceberg and looseleaf types. Some lettuces (especially iceberg) have been specifically bred to remove the bitterness from their leaves. These lettuces have a high water content with very little nutrient value. The more bitter lettuces and the ones with pigmented leaves contain antioxidants . Breeding L. sativa can easily be bred with closely related species in Lactuca such as L. serriola, L. saligna, and L. virosa, and breeding programs for cultivated lettuce have included those species to broaden the available gene pool.

Starting in the 1990s, breeding programs began to include more distantly related species such as L. tatarica. Nutrition Lettuce is a fat free, low calorie food. It is a valuable source of vitamin A and folic acid . Lactucarium (or “Lettuce Opium”) is a mild opiate-like substance that is contained in all types of lettuce. Both the Romans and Egyptians took advantage of this property eating lettuce at the end of a meal to induce sleep. Religious restrictions Lettuce (Lactuca sativa) | Vegetables Gardening Lettuce (Lactuca sativa) Gardening [an error occurred while processing this directive] Lettuce (Lactuca sativa) is a species of temperate annual or biennial leaf vegetable in the family Asteraceae. It is commercially grown worldwide, and is most frequently used in salads or as side dishes. The genus name is derived from Latin word' Lac' which means milk, in referring to the plant's milky juice. Lettuce plant has a rosette growth habit with a short stem.

The stem and branches gradually adding their length and produce many flower heads that looked like those of dandelions, but smaller, in a process known as bolting. Lettuce is usually harvested before it bolts. Lettuce grows well in light, sandy, fertile, humus-rich and moist soil. It prefer cool weather with day temperature below 75 degrees Fahrenheit, and night temperature above 40 degrees Fahrenheit. Sunny, hot and dry conditions may cause the plant to turn bitter, and bolting (produce a flower shoot). Lettuce is often grown as catch crop, plant between rows of slower-growing plant, like Brussels sprout or broccoli. There are six recognised cultivar groups of lettuce, arranged by the head formation and leaf structures. Butterhead (L. sativa var. capitata) - The cultivar group has loose head and buttery textured leaves. It is very popular in Europe. Among the popular varieties are Buttercrunch, Bibb, Boston and Tom Thumb. Chinese lettuce (L. sativa var. asparagina) - This cultivar group is a non-head forming type, with long, sword-shaped leaves.

The leaves has a bitter and robust flavor, usually used in stir-fried dishes, stews and also as a garnish. Chinese lettuve cultivars can be divided into leaf-used (known in chinese as 'youmaicai'), stem-use (known as celtuce), or shengcai (literrally means raw vegetable). Crisphead or Iceberg - This cultivar group is the mildest of all lettuces, forming tight, dense, cabbage-like head. It is valued for its juicy, crunchy texture of its leaves. Looseleaf (L. sativa var. crispa) - This cultivar group has delicate, tender, and mildly-flavored leaves. Oak leaves and lollo rosso lettuces are included in this group. Romaine or Cos (L. sativa var. romana) - This cultivar group is heat tolerant, and has a firm rib at the center, with long head of sturdy leaves. Summer Crisp (Batavian) - This cultivar group is an intermediate between Iceberg and Looseleaf. It forms moderately dense head and crunchy-textured leaves.

Lettuce is low in calories, and high in vitamin A, C, K, folic acid and iron. It naturally absords and concentrates lithium. Different cultivars of lettuce Lettuce - Phadia - Setting the Standard - Phadia.com Common names: Lettuce, Garden lettuce Main types: L. sativa var. capitata - Head Lettuce L. sativa var. asparagina - Stem Lettuce. L. sativa var. crispa - Leaf Lettuce. L. sativa var. longifolia - Romaine. There are more than 100 varieties of Lettuce and salad greens. This family contains many weeds of great importance in allergy, e.g., Mugwort and Ragweed. Allergen Exposure Geographical distribution Probably the world’s most widely used salad vegetable, Lettuce is thought to have originated in the Mediterranean region in the form of Prickly lettuce. It is recorded as having been served in Persia in 400 BC. Annual and biennial Lettuce is cultivated in many parts of the world for its edible leaves.

Of the many varieties, basic forms have been classified as follows: heading or head varieties, cutting or leaf varieties, and Cos or Romaine. A fourth, very minor type, is the so-called Stem, Celery or Stalk Lettuce. Environment Lettuce grows in cultivated beds. Its most common use – as leaves, but sometimes also as spouted seeds – is in salads and sandwiches, but it may also appear in soups and stews. Edible oil is obtained from the tiny seeds, but extraction of the oil on any scale would not be feasible. The sap of the plant contains lactucarium, which is used in medicine and folk medicine for its anodyne, antispasmodic, digestive, galactogogue, diuretic, hypnotic, narcotic, sedative, anaphrodisiac, carminative, emollient, febrifuge, hypoglycaemic, and parasiticide properties. Lactucarium has the effects of a feeble opium, but without tendency of opium to cause digestive upsets; nor is lactucarium addictive.

It is taken internally in the treatment of insomnia, anxiety, neuroses, hyperactivity in children, dry coughs, whooping cough, rheumatic pain, etc. The sap has also been applied externally in the treatment of warts. Even normal doses can cause drowsiness, while excess doses cause restlessness, and overdoses can cause death through cardiac paralysis. Allergens Four protein bands with molecular weights of 50, 43, 39 and 16 kDa have been detected in Lettuce, and these exhibited IgE-binding properties (1). A second study reported detecting 14 allergens in Iceberg lettuce, with weights between 13 and >113 kDa (2). A 42-year-old female presented with widespread erythema and a subsequent episode of anaphylaxis after ingesting “Tudela” lettuce hearts (Lactuca sativa var.); serum from this patient revealed several bands, predominantly in the range of 15–65 kDa (3). Researchers have reported predominant reactivity to a protein of 42-48 kDa (4-6).

The following allergen has been characterised: Lac s 1, a 9 kDa lipid transfer protein (7-8). Two Lac s 1 isoforms were identified, with an amino-acid identity of 62% to each other, up to 66% to Pru p 3 from Peach, and 72% to the N-terminal peptide of the London plane pollen LTP Pla a 3. The prevalence of IgE binding to nLac s 1 was 90%, as shown in immunoblotting experiments with Lettuce extract (8). No differences in the protein profiles of several Lettuce varieties (Chicory, Butterhead, Iceberg, [mini]-Romaine, Frisée) were found, or between younger (inner) and older (outer) leaves, but the authors could not exclude slight differences in the level of LTP accumulation in the leaves (8). IgE binding to a 24 kDa protein and HMW proteins (> 50 kDa) was due to cross-reactive carbohydrate determinants (CCDs) (8).

Potential cross-reactivity An extensive cross-reactivity among the different individual species of the genus could be expected, as well as to a certain degree among members of the family Asteraceae (9). A patient allergic to Chicory reported reactions to botanically related Endive (Cichorium endivia) and Lettuce (Lactuca sativa). No cross-reactivity was found with pollen from Mugwort, a member of the same family (6). This is contradicted by a report on subjects allergic to Artemisia, who appeared to be at a higher risk of concomitant sensitisation to various foods, including Lettuce. A common allergen may be responsible (10). Four patients with occupational contact dermatitis to Lettuce were shown to be cross-reactive with endive (11). Lettuce contains a lipid transfer protein (Lac s 1), which may result in cross-reactivity with other lipid transfer protein-containing foods (12). Lac s 1 was shown to have a high amino acid sequence identity with other lipid transfer proteins, from Peach and Cherry, among others.

A clear partial cross-reactivity was observed between Lettuce LTP and London plane tree- (Platanus) pollen extract (7). Although a partial IgE cross-reactivity between Lac s 1 and Platanus pollen exists, a more pronounced cross-reactivity occurs with the LTPs from the Rosaceae family, e.g., Pru av 3 from Cherry (13), and Pru p 3, the major allergen from Peach (14-15). Lac s 1 also showed broad IgE cross-reactive properties with Walnut and Peanut extract (16), LTPs from Mugwort and Chestnut (17-18). Vit v 1 from Grape (19), Zea m 14 from Maize (20), Cor a 8 from Hazelnut (21), and Mal d 3 from Apple (22). Although the highest degree of sequence identity of the N-terminus of Lac s 1 was found with Mal d 3, only a single subject in the Lettuce-allergic group reported Apple allergy (7). The authors therefore postulated a lack of correlation between sequence identity and clinical cross-reactivity (7-8).

RAST inhibition demonstrated that Carrot does share allergens with Lettuce, although Carrot allergens are more potent than those of Lettuce (2). One study concludes that cross-reactivity was observed between Platanus acerifolia pollen and plant-derived foods. OAS in these patients may have been caused by primary respiratory sensitisation to Plane tree pollen, and the authors propose profilin as the cause. Approximately 22% of the Spanish patients with Plane tree pollen allergy and food allergy had allergy to vegetables, including Lettuce (23). Clinical Experience IgE-mediated reactions Lettuce allergy is not frequently reported in the literature, but is found in clinical practice, predominantly in the southern part of Europe (8). Lettuce may induce symptoms of food allergy, in particular oral allergy syndrome, in sensitised individuals (1-5,7-8,12,23-24). Adverse reactions may be severe, resulting in anaphylaxis (7). Lettuce and Carrot can account for clinically significant IgE-mediated allergic reactions, including prolonged nasal obstruction (25).

This finding is supported by a Mexican study, in which, among 1,419 allergic patients aged between 1 and 18 years, 442 (31%) had positive skin prick test (SPT) results to 1 or more among 33 tested foods. Fish, milk, seafood, beans, Orange, Onion, Tomato, Chicken, nuts, Lettuce and Strawberry were responsible for 58% of the total of allergic reactions. Of those, fish, milk, seafood, Soy and Orange (39%) had the highest frequency (26). In a study of 29 Lettuce-allergic patients, with or without concomitant Peach allergy, and 19 Peach-allergic patients without Lettuce allergy, it was concluded that the data provided indirect evidence that Pru p 3, a lipid transfer protein, might act as the primary sensitising agent in patients allergic to both Lettuce and Peach. Of those with Lettuce allergy, anaphylaxis was reported in 15, gastrointestinal symptoms in 2, OAS in 8, urticaria in 3, and angioedema in 3.

Skin prick testing was positive in 17, and prick to prick testing in 18, (a number of SPT-positive cases were prick to prick-negative, and vice versa); IgE antibody levels for Lettuce were negative in 7, and for nLac s 1 negative in 2 but positive in 27 of the 29 (8). A study of 14 patients with allergy to Lettuce described how all were sensitised to Platanus pollen. Ten were allergic to a lipid transfer protein in Lettuce. Fifty percent of the subjects experienced anaphylaxis to Lettuce. Symptoms of oral allergy syndrome was followed by more severe symptoms in the majority of cases. Lac s 1, the lipid transfer protein, was the responsible allergen (7). A 42-year-old female presented with widespread erythema with pruritus after ingesting “Tudela” lettuce hearts (Lactuca sativa var.). She experienced an anaphylactic shock episode a few days later after eating the Lettuce hearts dressed with Olive oil. She had concomitant seasonal rhinitis, which coincided with the pollination of Platanus acerifolia.

Skin prick tests were positive to “Tudela” lettuce heart, Lettuce, endive, pollen from P. acerifolia and Artemisia vulgaris; but negative to Leek, Potato, Carrot and Latex. In spite of her tolerating the ingestion of Leeks, Potatoes and Carrots, presence of IgE antibodies to these foods was demonstrated (3). However, IgE antibodies may be found in asymptomatic patients. Skin-sensitising allergens have been identified, but reactions do not appear to be IgE-mediated (27). Food-dependent exercise-induced anaphylaxis has been reported (28-29). Generalised, pruritic, papular and erythematous eruption, associated with facial and lingual oedema and a tight throat, due to Lettuce, has been documented in a patient (1). Previously unsuspected Lettuce allergy in a patient with delayed metal allergy has been reported (30). Other reactions Occupational eczema or contact dermatitis, combining delayed and immediate-type reactions, has been reported (11,31-34), including contact hypersensitivity to Lettuce in a chef (35).

A 35-year-old woman complained of an itchy rash on her fingers, which occurred for the first time 3 months after commencing work at a vegetable packing plant. The rash then spread to her arms and neck. Despite a negative standard battery, targeted patch testing revealed Lettuce as the offending agent (36). Greenhouse workers and gardeners are at risk of Compositae-related allergy to Chrysanthemum (Dendranthema), Daisy (Argyranthemum frutescens) and Lettuce (Lactuca sativa) (37-38). Ingestion of Lettuce was reported to result in lip and facial swelling, and in aggravation of pre-existing Compositae dermatitis (39). Other substances, including allergens, may be present that result in adverse effects. Powdered Latex glove use in salad preparation may result in measurable amounts of Latex protein on Lettuce, with an exposure-dependent increase in the Latex protein levels (40).

Sulphite-treated Lettuce (sulphite is used as a preservative) is capable of provoking bronchospasm in sulphite-sensitive asthmatics and may be a cause of restaurant-provoked asthma in these individuals (41). Lettuce contains high levels of naturally occurring nitrates (42-43). Compiled by Dr Harris Steinman, harris@zingsolutions.com References Vila L, Sanchez G, Sanz ML, Dieguez I, Martinez A, Palacios R, Martinez J. Study of a case of hypersensitivity to lettuce (Lactuca sativa). Clin Exp Allergy 1998;28(8):1031-5 Helbling A, Schwartz HJ, Lopez M, Lehrer SB. Lettuce and carrot allergy: are they related? Allergy Proc 1994;15(1):33-8 Olive-Perez A, Pineda F. Anaphylactic reaction to ’Tudela’ lettuce hearts.

Allergy 2003;58(11):1205-6 Franck P, Kanny G, Dousset B, Nabet P, Moneret-Vautrin DA. Lettuce allergy. Allergy 2000;55(2):201-2 Escudero A, Bartolome B, Sanchez-Guerrero IM, Palacios R. Lettuce and chicory sensitization. Allergy 1999;54(2):183-4 Cadot P, Kochuyt AM, Deman R, Stevens EA. Inhalative occupational and ingestive immediate-type allergy caused by chicory (Cichorium intybus). Clin Exp Allergy 1996;26(8):940-4 San Miguel-Moncin M, Krail M, Scheurer S, Enrique E, Alonso R, Conti A, Cistero-Bahima A, Vieths S. Lettuce anaphylaxis: identification of a lipid transfer protein as the major allergen.

Allergy 2003;58(6):511-7 Hartz C, San Miguel-Moncin MM, Cistero-Bahima A, Fotisch K, Metzner KJ, Fortunato D, Lidholm J, Vieths S, Scheurer S. Molecular characterisation of Lac s 1, the major allergen from lettuce (Lactuca sativa). Mol Immunol 2007;44(11):2820-30 Yman L. Botanical relations and immunological cross-reactions in pollen allergy. 2nd ed. Pharmacia Diagnostics AB. Uppsala. Sweden. 1982: ISBN 91-970475-09 Garcia Ortiz JC, Cosmes PM, Lopez-Asunsolo A. Allergy to foods in patients monosensitized to Artemisia pollen. Allergy 1996;51(12):927-31 Krook G. Occupational dermatitis from Lactuca sativa (lettuce) and Cichorium (endive).

Contact Dermatitis 1977;3(1):27-36 Asero R, Mistrello G, Roncarolo D, Amato S. Detection of some safe plant-derived foods for LTP-allergic patients. Int Arch Allergy Immunol 2007;144(1):57-63 Scheurer S, Pastorello EA, Wangorsch A, Kastner M, Haustein D, Vieths S. Recombinant allergens Pru av 1 and Pru av 4 and a newly identified lipid transfer protein in the in vitro diagnosis of cherry allergy. J Allergy Clin Immunol 2001;107(4):724-31 Lleonart R, Cistero A, Carreira J, Batista A, Moscoso del Prado J. Food allergy: identification of the major IgE-binding component of peach (Prunus persica).

Ann Allergy 1992;69(2):128-30 Pastorello EA, Farioli L, Pravettoni V, Ortolani C, Ispano M, Monza M, Baroglio C, Scibola E, Ansaloni R, Incorvaia C, Conti A. The major allergen of peach (Prunus persica) is a lipid transfer protein. J Allergy Clin Immunol 1999;103(3 Pt 1):520-6 Asero R, Mistrello G, Roncarolo D, Amato S, Caldironi G, Barocci F, Van Ree R. Immunological cross-reactivity between lipid transfer proteins from botanically unrelated plant-derived foods: a clinical study. Allergy 2002;57(10):900-6 Pastorello EA, Pravettoni V, Farioli L, Rivolta F, Conti A, Ispano M, Fortunato D, Bengtsson A, Bianchi M.

Hypersensitivity to mugwort (Artemisia vulgaris) in patients with peach allergy is due to a common lipid transfer protein allergen and is often without clinical expression. J Allergy Clin Immunol 2002;110(2 Pt 1):310-7 Diaz-Perales A, Lombardero M, Sanchez-Monge R, Garcia-Selles FJ, Pernas M, Fernandez-Rivas M, Barber D, Salcedo G. Lipid-transfer proteins as potential plant panallergens: cross-reactivity among proteins of Artemisia pollen, Castanea nut and Rosaceae fruits, with different IgE-binding capacities. Clin Exp Allergy 2000;30(10):1403-10 Pastorello EA, Farioli L, Pravettoni V, Ortolani C, Fortunato D, Giuffrida MG, Perono Garoffo L, Calamari AM, Brenna O, Conti A. Identification of grape and wine allergens as an endochitinase 4, a lipid-transfer protein, and a thaumatin.

J Allergy Clin Immunol 2003;111(2):350-9 Pastorello EA, Farioli L, Pravettoni V, Ispano M, Scibola E, Trambaioli C, et al The maize major allergen, which is responsible for food-induced allergic reactions, is a lipid transfer protein. J Allergy Clin Immunol 2000;106(4):744-51 Pastorello EA, Vieths S, Pravettoni V, Farioli L, Trambaioli C, et al. Identification of hazelnut major allergens in sensitive patients with positive double-blind, placebo-controlled food challenge results. J Allergy Clin Immunol 2002;109(3):563-70 Sanchez-Monge R, Lombardero M, Garcia-Selles FJ, Barber D, Salcedo G. Lipid-transfer proteins are relevant allergens in fruit allergy.

J Allergy Clin Immunol 1999;103(3 Pt 1):514-9 Enrique E, Cistero-Bahima A, Bartolome B, Alonso R, San Miguel-Moncin MM, Bartra J, Martinez A. Platanus acerifolia pollinosis and food allergy. Allergy 2002;57(4):351-6 Alonso R, Enrique E, Pineda F, Basagaña M, San Miguel-Moncín MM, Bartra J, Palacios R, Cisteró-Bahíma A. An observational study on outgrowing food allergy during non-birch pollen-specific, subcutaneous immunotherapy. Int Arch Allergy Immunol 2007;143(3):185-9 Schwartz HJ, Arnold JL, Strohl KP. Nasal response to carrot and lettuce challenge in allergic patients.

Ann Allergy Asthma Immunol 1995;74(2):152-4 Avila Castanon L, Perez Lopez J, del Rio Navarro BE, Rosas Vargas MA, Lerma Ortiz L, Sienra Monge JJ. Hypersensitivity detected by skin tests to food in allergic patients in the Hospital Infantil de Mexico Federico Gomez. [Spanish] Rev Alerg Mex 2002;49(3):74-9 Hausen BM, Andersen KE, Helander I, Gensch KH. Lettuce allergy: sensitizing potency of allergens. Contact Dermatitis 1986;15(4):246-9 Romano A, Di Fonso M, Venuti A, Palmieri V, Zeppilli P. Food-dependent exercise-induced anaphylaxis: report of two cases. Int J Sports Med. 1992;13(8):585-7 Romano A, Di Fonso M, Giuffreda F, Quaratino D, Papa G, Palmieri V, Zeppilli P, Venuti A. Diagnostic work-up for food-dependent, exercise-induced anaphylaxis.

Allergy 1995;50(10):817-24 Fregert S, Sjoborg S. Unsuspected lettuce immediate allergy in a case of delayed metal allergy. Contact Dermatitis 1982;8(4):265 Veien NK, Hattel T, Justesen O, Norholm A. Causes of eczema in the food industry. Derm Beruf Umwelt 1983;31(3):84-6 Alonso MD, Martin JA, Cuevas M, Parra F, Lezaun A, Conde Salazar L, Guimaraens MD, Losada E. Occupational protein contact dermatitis from lettuce. Contact Dermatitis 1993;29(2):109-10 Helander I. Contact dermatitis to lettuce. Contact Dermatitis 1984;11(4):249 Jovanović M, Poljacki M. Compositae dermatitis. [Croatian] Med Pregl 2003;56(1-2):43-9 Mitchell D, Beck MH, Hausen BM.

Contact sensitivity to lettuce in a chef. Contact Dermatitis 1989;20(5):398-9 Gottschalk G, Todd G. Lettuce allergy. Current Allergy and Clinical Immunology 2005;18(3):144-6 Paulsen E, Sogaard J, Andersen KE. Occupational dermatitis in Danish gardeners and greenhouse workers (III). Compositae-related symptoms. Contact Dermatitis 1998;38(3):140-6 Paulsen E, Andersen KE, Hausen BM. Sensitization and cross-reaction patterns in Danish Compositae-allergic patients. Contact Dermatitis 2001;45(4):197-204 Oliwiecki S, Beck MH, Hausen BM. Compositae dermatitis aggravated by eating lettuce.

Contact Dermatitis 1991;24(4):318-9 Explore Cornell - Home Gardening - Vegetable Growing Guides - Growing Guide Vegetable Growing Guides Vegetable (Cool Season) - Salad Greens Lactuca sativa Asteraceae Family With the variety of colors, shapes and flavors available, your salads may never be the same. Lettuce is adapatable to many growing conditions, but likes it cool - around 60 F to 65 F. Grow in spring and fall, and slow bolting by shading summer crops. Yields best in full sun. Part shade helpful when it’s hot. Soil conditions: requires well-drained soil Tolerant of a wide range of soils, but prefers well-drained, cool, loose soil with plentiful moisture and pH 6.2 to 6.8. Sensitive to low pH. Lime to at least 6.0. Special locations: Height: 0.5 to 2 feet Spread: 0.5 to 2 feet Foliage color: Shape: cushion, mound or clump Romaine (Cos) varieties tend toward upright. Special Considerations frost - Will withstand light to moderate frost.

Hardened seedlings more tolerant than mature plants. Special characteristics: not native to North America - Mediterranean origin. Was cultivated by Egyptians 6,500 years ago. Special uses: How to plant: Propagate by seed Germination temperature: 40 F to 85 F - Seed can go dormant at high temperatures. Best germination is below 70 F. Days to emergence: 7 to 14 - Germinates in about a week at 50 F, 2 days at 70 F. Seed can be saved 1 year. Maintenance and care: Direct seed or transplant in early spring, as soon as you can work the soil. To get an early start, prepare beds the previous fall by working in manure or compost and raking smooth to leave a fine seedbed. Direct-seeding: Sow seed 1/8 inch deep, 1 inch apart in rows 12 to 18 inches apart. When plants have two or three true leaves, thin to 12-inch spacings for crisphead varieties, 6 to 10 inches for other types. You can also lightly broadcast seed (particularly of looseleaf varieties) in a patch instead of a row.

Transplants: Sow in 1-inch cells 3 to 4 weeks before transplanting outside. Harden seedlings by reducing water and temperature for 3 days before transplanting. Hardened plants should survive 20 F. Space crisphead transplants 12 inches apart in rows 18 inches apart. Space other varieties 6 to 10 inches apart in rows 12 to 18 inches apart. Seeds need light to germinate, so do not plant too deep. Make succession plantings every week or two. Grow several varieties with different maturity dates for a continuous supply. Lettuce has a shallow root system. Keep soil moist to keep plants growing continuously. Mulch to retain moisture and suppress weeds (unless slugs are a problem). Moisture stress and high temperatures, particularly at night, encourage bolting. As the season progresses, plant more bolt-resistant varieties. Locate plants where they will be partially shaded by taller nearby plants, latticework or other screen. Use row covers to protect very early plantings from cold, to protect young plants from insects, and (supported by hoops) to shade crops when warm weather arrives. For fall crops, time maturity around time of first expected frost.

Mature plants aren’t as tolerant of freezing as seedlings. Pests: Lettuce Click here to email us. Lettuce Sponsored link/s: Cultivars Even in winter, but of course especially in summer, a good salad is a treat for body and soul. And, while specialty salads--from a fresh sliced tomato with a little chive, parsley, olive oil, and vinegar to a beet-and-walnut salad--are many and pleasing, lettuce remains the bedrock of the salad-lover's crops. But there are lettuces and there are lettuces . . . . Lettuce Types There are a myriad of lettuce types, differing one from another in ways large and small. The most useful high-level classification is this: Heading lettuces, commonly called "iceberg lettuce" (cultivar Summertime shown): Everyone recognizes these, familiar from supermarket shelves and cafeteria sandwiches. Curiously, the type is quite modern, having been developed only a half century or so ago.

Compared to all other lettuces, they require more growing space, have longer growing times, are more likely to bolt, are more susceptible to pests and diseases, have less nutritive value, and--by general agreement--have notably less flavor; naturally, they are America's favorite kind (though not the rest of the world's). Romaine lettuces, also called Cos lettuces (cultivar Jericho shown): This is a type known since, at the very least, Roman times. It achieved fame in America with the popularity of the "Caesar Salad". It has a more distinct and distinctive taste than most other lettuces, a very faintly bitter quality typical of flavored salad greens. Batavian lettuces (cultivar Magenta shown): This wonderful type is scandalously unknown in the U.S. It is perhaps the hardiest of all lettuce types, withstanding summer heat excellently and, by most reports, winter cold as well. Moreover, many think it the best-tasting type of lettuce (sounds a no-brainer, doesn't it?) On the whole, the type is perhaps best described as "semi-heading"--it doesn't form a true head, but is not looseleaf either.

But individual varities are fairly variable, some heading more distinctly than others. Butterhead (or Buttercrunch or Bibb) lettuces (cultivar Adriana shown): These heat-hardy and gorgeous leafy rosettes are as good eating as they are delightful to look at. They are also sometimes called "Boston" or "limehead" lettuces. Smaller ones are often used entire as one-person salads (they go wonderfully with a few mushrooms and a simple vinegrette). They are the most popular type in Europe. Looseleaf lettuces (cultivar Red Sails shown): A type which scarcely needs explanation. Within each broad type there are numerous variants, but we like to think of each as being divided into two sub-classes: "green" and "red"--where "red" rarely means more than purple-tinged or bronze (as with the "red" Sierra Batavian pictured above). Choosing Cultivars Summer Varieties With some moderate care in the handling of our growing area--as described farther down this page--one should be able to grow lettuce all the year round. Lettuce is a cool-weather crop to begin with, and is pretty cold-hardy.

While it certainly can't grow out in the snow, only modest aid should be needed to keep it going. More difficult is summer growing, as lettuces notoriously bolt (go to seed) very quickly in hot weather. The answer there is (we hope and believe) modest protection, such as partial shading, but first and foremost careful selection of cultivars known to be heat-resistant. A great help here are the results from the Colorado State University's Lettuce Bolting Resistance Project . We don't have to rely on seedmen's claims or individual anecdotal accounts: we have careful, methodic trial results available. Regrettably, not all the cultivars their results point at remain readily available to home gardeners, but fortunately there are either clear successors or broadly applicable results, so we are satisfied with the list we have arrived at. It's a great shame that the former outstanding lettuces home-garden seedsman, A Cook's Garden, was sold by the Ogdens and is no longer anything special for lettuce and other salad-makings seeds; but Johnny's, in Maine, has evolved into a pretty good replacement, and many of our selections are unique to that seedsman.

(We don't normally discuss sources on these pages, reserving that for our Seed Sources page, but here one cannot escape the subject.) Broadly speaking, the Batavians are the undisputed kings of heat resistance, far ahead of all other types; runners up are the butterhead types. In summer (or really warm parts of spring and autumn), it seems just folly to try growing any other varieties; indeed, in the peak-heat days, even butterheads are probably best avoided. (A ways back are the romaines; leafy types don't do well; and heading lettuces are notoriously intolerant of really hot summer conditions--besides, we already know that they are scarcely worth the home gardener's putting her or himself out for.) The best Batavian types for summer uses are green Nevada (widely available) and red Magenta, an improved selection of the classic Sierra (Magenta is sufficiently available).

For butterhead types, the best green is surely the Israeli-bred Ben Shemen (now available, so far as we know, only from Bountiful Gardens); the red type Fireball has apparently disappeared from the market, and we are unsure what might make a good substitute (or you could just do with green, especially since you may not be able to manage butterheads at all). For the stubborn, who want to see if they can defy the odds, the best summer Romaine types are probably green Jericho (sufficiently available) and the red Cimmaron--also listed as Cimmarron (widely available). Looseleafs and heading types are wasted effort in heat. Winter Varieties Though seed houses make much of certain "cold-hardy" winter lettuces, in truth all lettuces are, by nature, fairly cold-hardy. Rather than shop for especially cold-hardy types (and thus have to have two sets of lettuce seeds, one for hot and one for cold), it makes more sense to try to ameliorate winter growing conditions, something we discuss a bit farther on.

Curiously, Batavians, so good in heat, are also pretty resistant to frost, as to some extent are butterheads--so one needn't look for special types of those other than the ones discussed above under "Summer". If your fancy for lettuce is insufficiently satisfied by Batavians, butterheads, and Romaines, you might as well pick whatever green and red looseleafs you feel good about (we suspect it's more a matter of appearance than anything else--we'd pay cash money to see someone reliably tell cut-up lettuce types apart in a blindfold three-corner taste test). And if you want a heading type, feel fancy-free there, too. For what it's worth, the British newspaper the Daily Telegraph rated looseleaf type Black-Seeded Simpson the best flavored--actually "best-flavoured"--lettuce in the UK.) In 2008, the Master Gardeners of Santa Clara County (California), a large, active group that often does vegetable trials, did a taste test of red looseleaf lettuces and selected Flame and Cardinale as tied for first, with Sunset and Bronze Arrow tied for second. Inquiring minds wanted to know, and now they do.

Oh, and also in the Telegraph was a reference to Reine de Glace as "the best of the Iceberg types". The Growing Area In spring and fall, lettuces can be grown outdoors with no special considerations. But if we are to succeed in the cold of winter and the heat of summer, we need to take some measures. Winter As we said above, lettuces are by nature cool-weather crops--they supposedly can withstand air temperatures down to perhaps as low as 20° F., so in a region where the average coldest overnight low is 17° F. (though we ourselves are in a "frost pocket" and can easily get down to zero or below), we don't necessarily need measures so drastic as an actual greenhouse. There are all sorts of "tunnel" and "hoop" systems , of varying degrees of complexity and sophistication (and cost), or you can fake it up on your own. Fortunately, lettuces grow pretty close to the ground, so plant height is not an issue.

Another helpful trick is to place transparent quart (or liter nowadays) soda bottles filled with water in among the plants; those will heat up in the sunny day and release the heat at night (a poor man's version of Walls o' Water, plus it doesn't surround the plant). Summer To mitigate the warmth, the simplest thing is to provide some shade. A crude way is simple latticed slats set up on the south, east, and west ends of your greens-growing bed. Or you can get fancier by putting up (in the same places) sunshade fabric, of the sort used on house outsides over windows in the summer; or perhaps plastic window-screen roll (fairly inexpensive) would work. If you get relentless sun, make the east and west end coverings solid (that assumes a bed laid out with its long axis easy-west). Planting Timing We will take it as an assumption that by the means described above, we in this climate can be growing lettuces throughout the year.

To simplify matters, we will also assume that each lettuce will be taken as a whole when ready, though in reality some are "cut and come agin" types from which we take leaves without pulling the whole plant; the idea is just to get a grasp on numbers. Let's say a typical lettuce spends 6 weeks outdoors in the lettuce bed after, say, two weeks indoors in a pot; that's about 8 weeks total growing time. From here on, the calculation is custom, depending on how often you need another head of lettuce. Just to make an example, suppose you think to yourself "oh, I guess one or two heads a week"; that translates to roughly another head every four days. Your own household needs might be anything from a new head every day to a head every eighth day--only you can say. But to continue the example: since the typical lettuce is ready in about eight weeks--56 days--from seeding, the number of heads you need space for is those 56 days divided by that 4 days, or--in this example--14. So a household that needs a new lettuce every fourth day would need space for 14 heads in its garden, and would be harvesting.

and simultaneously starting new seed, every fourth day. Obviously, that is all very rough: lettuces do not have the same growth period for all types (or, for that matter, for any two seeds out of the same packet), household needs are not exact and cna go up or down with the season or individual tastes, some lettuces are more productive than others, some are take-the-head while others are cut-and-come-again, and we might want different mixes in our salad bowls from time to time. All that said, though, we need some idea of how much, on average, we're likely to need, and that's the way to reckon it. Starting Seedlings Around here, we always start lettuces indoors as seedlings for transplanting. Sow into 1" seed cells or the like; use 2 or 3 seeds for each seedling wanted, then cull the weakest before they get too crowded. Don't let the seeds or seedlings get too warm: try to keep them below 65° in one way or another, and at all costs below 75°.

Be sure to carefully harden off the seedlings: for 2 to 3 days before transplanting, reduce their water and the ambient temperature--that is especially important in the stressful days of low winter and of high summer. The Bed Lettuces are "greedy feeders", so be sure that the soil is good and rich for them. Something like 1 to 1½ pounds a square foot of compost or well-composted steer manure every year or two is a good idea (that's a layer about ½ to 1 inch thick). Though we hope to get lettuces (and other salad greens ) growing year round, it's wise to move the lettuce bed at least annually, to minimize soil-disease risks--our own plan is two identical beds, each used for a year while the other is either fallow or used for some non-greens (and non-cole and non-solanaceae) catch crop. Transplanting Out Wait 3 to 4 weeks after sowing before transplanting out; 4 weeks is probably best in the high-stress summer and winter periods, whereas 3 weeks will likely be OK in spring and autumn.

When starting a new bed, space the new lettuces at about a foot; in the winter, though, you might make that more like 10 or even 9 inches, as they will grow more slowly and likely a little smaller (it's not a matter of saving space, but of trying to keep the mature plants' leaves just touching, as the proverbial "living mulch".) After the bed is fully planted, whenever you remove a head of lettuce from the bed, just replace it with the largest seedling you have growing indoors. Plants are not factory-made: they grow at different paces, both as seedlings and as plants, so don't assume that the order in which you sow seed is necessarily the exact order in which you will transplant out (or that your transplanting order is the exact order in which you will harvest). Growing Keep them watered well and, perhaps above all, regularly. Irregular watering may be worse than scanty watering. Pick lettuce when it looks ready. Grow enough that you can afford to pick when the individual plants are of a modest size, lest you run the risk of having them bolt on you.

Many leafy kinds can be harvested a few leaves at a time, which they will then grow back--what's called "cut and come again" harvesting. More Relevant Links Besides any links presented above on this page, the following ought to be especially helpful. Plants For a Future Database: Lettuce - the main page for "lettuce": there are other pages (linked below) for certain particular types Lettuce varieties for home growing - from New Zealand: while their selections of particular types are now a little dated, the discussion of the basic classes is excellent Odds and Ends Biology All the lettuces are from the Asteraceae (formerly Compositae) family, the asters, which includes many edible greens and some edible roots. History There are today literally thousands of different cultivars of lettuce--all sprung from ancestral wild lettuces that grew (and still grow) in Northern Europe, Asia, North Africa, and even parts of North America. There is good evidence that some sorts of lettuces were being cultivated in Egypt as early as 4500 B.C. Certainly the Babylonians were cultivating it by 3,000 years ago, and the Chinese may have started growing it before them.

Herodotus tells us that lettuce was served on the tables of the Persian kings of the 6th century B.C. In the 5th and 4th centuries B.C., other great Greek writers described and praised its virtues. The Greeks called it tridax, the Persians kahn. The plant's modern "scientific" (Latin) name, Lactuca, is derived from the Latin root word lac, milk; our English word "lettuce" derives from the French laitue, also meaning milk. That, obviously, is because the plant has a heavy, milky juice. The juice, or sap, was long thought to have significant medical properties: Hippocrates mentions lettuce sap as a medicinal, supposed to induce sleepiness. By the first century after Christ, Roman writers were describing a dozen distinctly different lettuce types, some of which were fairly common; it is known that lettuces much resembling present-day Romaine cultivars were then being grown.

(It was popularly believed in the time of Augustus that he was cured of an illness by eating lettuce.) As in the development of the cabbages, the primitive forms of lettuce were loose, leafy, and sometimes "stemmy" types; the looseheading and firm-heading forms occurred much later. Firm-heading forms had become well developed in Europe by the 16th century, but just when they were first developed is unknown. The oak-leaved and curled-leaf types, and various other colors now known, were all described in the 16th and 17th centuries in Europe. Columbus evidently carried lettuce to the New World, for its culture was reported on Isabela Island (now called Crooked Island) in the Bahamas in 1494. It was common in Haiti in 1565. When it was introduced into South America is not known, but doubtless it was soon after the Europeans arrived; it was under cultivation in Brazil before 1650.

Lettuces are today used almost exclusively raw, but they can be cooked--indeed, lettuce was normally eaten cooked till the time of Louis XVI, when the Chevalier d'Albignac famously dressed raw lettuce with a vinaigrette. Envoi Think lettuce, for all its virtues, is boring? Check out The Lettuce Ladies (this being the 21st century, female readers can check out The Broccoli Boys , on the same page). LETTUCE | Vahrehvah article Mail Every thing about LETTUCE | Vahrehvah : Lettuce botanically known as Lactuca sativa is a binennial plant from the daisy family Asteraceae. It is most often grown as a leafy vegetable and can be eaten either raw or included in salads, sandwiches, hamburgers, tacos . Lettuce could also be added to many other dishes or cooked as in Chinese cuisine, which the stem becomes just as important as the leaf. Both the English name and the Latin name of the genus are ultimately derived from lac, the Latin word for “milk”, referring to the plant’s milky juice.

Mild in flavor, it has been described over the centuries as a cooling counterbalance to other ingredients in a salad . The lettuce plant has a short stem initially (a rosette growth habit), but when it gradually blooms, the stem and branches lengthen and produce many flower heads that look like those of dandelions, but smaller. This is referred to as bolting. When grown to eat, lettuce is harvested before it bolts. Lettuce is used as a food plant by the larvae of some Lepidoptera. Lettuce is grown commercially worldwide, requiring light, sandy, humus-rich, moist soil. It is normally grown by early and late sowing in sunny positions, or summer crops in shade. Ideally, lettuce plants require a rich, humous-laden soil that will hold moisture in the summer. They may require the soil to have lime added as a soil pH of 6.5 is just right. Quite often though, lettuce is grown between rows of slower growing plants like brussel sprouts or broccoli etc. This is called a catch crop. Water is a vital ingredient and lettuce prefers the soil to be moist at all times.

Lettuce plants do not like hot sunny conditions, preferring a lightly shaded site for summer varieties. The earliest depictions of lettuce were seen in the carvings of the Senusret I temple at Karnak. Lettuce was considered an aphrodisiac food in Ancient Egypt. Later, Ancient Greek physicians believed lettuce could act as a sleep inducing agent. The Romans cultivated it, and eventually made its way to the Papal Court at Avignon, France. Christopher Columbus introduced lettuce to the New World. There are six commonly recognized cultivar groups of lettuce that includes the Butterhead (Leaves have a buttery texture), Chinese lettuce (generally have long sword shaped, non head forming leaves bitter and robust flavor.

Used in stir- fried dishes and stews), Crisphead also called Iceberg (resembles a cabbage , generally t also called he mildest of the lettuces, valued more for their crunchy texture than flavor), Looseleaf (is tender, delicate and mildly flavored leaves), Romaine also called as Cos (leaves with firm rib down the center and is tolerant to heat unlike other lettuces) and finally the Summer Crisp also called Batavian (forms moderately dense heads with a crunchy texture and are intermediate between iceberg and looseleaf types). Some lettuces (especially iceberg) have been specifically bred to remove the bitterness from their leaves. These lettuces have high water content and so are less "nutritionally dense" than are the more bitter lettuces and those with darker leaves . While all lettuces contain antioxidants and Vitamin K, romaine and looseleaf lettuce contain five to six times the Vitamin C and five to ten times the Vitamin A of iceberg. Romaine and butterhead lettuce are good sources of folate. Lettuce naturally absorbs and concentrates lithium Lettuce is a low calorie food and is a source of vitamin A and folic acid. Iceberg lettuce is the most popular lettuce in the United States.

It is a head lettuce that is also low in nutritional value and flavor. Because of its superior shipping qualities, iceberg has been most available which accounts for it popularity. The most abundant nutrient in iceberg lettuce is water. Dark green lettuce leaves always indicate higher fiber, flavor and nutritional value. Lettuce is a cool weather crop. It can be divided into two categories; head lettuce and leaf lettuce. Leaf lettuce and romaine provide flavor and crunch and are excellent for salad and sandwich selections. Lettuce leaves should be free of wilt, rot and rust. Harvest crisp green leaves. Wrap fresh, unwashed leaves in plastic warp and store in the refrigerator. Avoid storing lettuce with apples , pears or bananas . These fruits release ethylene gas, a natural ripening agent that will cause the lettuce to develop brown spots and decay quickly. Toss lettuce that looks slimy or has black spots. The slime is the residue of bacterial decomposition and the black spots are usually mold. The nutritional value of lettuce varies with the variety. Lettuce in general provides small amounts of dietary fiber, some carbohydrates , a little protein and a trace of fat. Its most important nutrients are vitamin A and potassium.

Lettuce, except iceberg, is also a moderately good source of vitamin C, calcium , iron and copper. The spine and ribs provide dietary fiber, while vitamins and minerals are concentrated in the delicate leaf portion. For optimal nutritional value, lettuce should be eaten while it is fresh and crisp. The mild flavor of fresh lettuce leaves are well complimented by fresh or dry herbs. Lettuce is the base for most of the green salads . The simplest way to appreciate a tossed green salad is with a vinaigrette dressing. Keep it simple. When the dressing becomes too complicated, the mild garden greens can be overpowered. As lettuce is pretty low in calories, it makes a perfect snack for all those trying to lose weight. Lettuce, being high in dietary fiber, aids digestion and is good for those suffering from constipation. The high magnesium content in lettuce makes it rich in reviving powers, in relation to muscular tissues, brain and the nerves. Those suffering from gastritis, gout, irritable bowel, obesity, sexual addiction, stress, tuberculosis, ulcers and urinary tract diseases might benefit from the regular consumption of lettuce.

The nutritional values per 100 gms of lettuce are: Carbohydrates: 2.2 g Dietary Fiber: 1.1 g Fats: 0.2 g Protein: 1.4 g Water: 96 g Vitamin A: 166 μg Folate (Vitamin B9): 73 μg Vitamin C: 4 mg Vitamin K: 24 μg Iron: 1.2 mg Energy: 10 kcal (60 kJ)

Question: Lactuca Sativa is the Latin name for which vegetable, which has varieties including Summercrisp, Butterhead and Romaine?
Answer: Lettuce