Depending on the variety, lettuce is an excellent source (20% of the Daily Value, DV, or higher) of vitamin K (97% DV) and vitamin A (21% DV) (table), with higher concentrations of the provitamin A compound, beta-carotene, found in darker green lettuces, such as romaine. It is very similar in look and medicinal effects to Wild Lettuce, Lactuca virosa. [9], The Romans referred to lettuce as lactuca (lac meaning dairy in Latin), an allusion to the white substance, now called latex, exuded by cut stems. (Did you know that lettuce is like a cousin-once-removed relative of dandelion? The cultivated variety appears to have been about 75 cm (30 in) tall and resembled a large version of the modern romaine lettuce. Plants that have produced a plump head or substantial greens throughout the season are likely flowering naturally and should be left to go to seed. It is most often grown as a leafy vegetable. Give it a try if you are interested. Lettuce spread to the Greeks and Romans; the latter gave it the name lactuca, from which the English lettuce is derived. Typically lettuce will flower when the temperature warms in late spring or early summer. It makes the process easier. [20] Scientific research into the genetic modification of lettuce is ongoing, with over 85 field trials taking place between 1992 and 2005 in the European Union and United States to test modifications allowing greater herbicide tolerance, greater resistance to insects and fungi and slower bolting patterns. So you could theoretically have a never ending supply of lettuce right in your kitchen. These are regarded as … Celtuce, a lettuce variety grown primarily in Asia for its stems, crosses easily with lettuces grown for their leaves. Continue cutting plants as needed, clearing a swath from one side of the bed to the other. Lettuce is generally a rich source of vitamins K and A, though the nutritional quality varies, depending on the variety. Lettuce was originally farmed by the ancient Egyptians, who transformed it from a plant whose seeds were used to create oil into an important food crop raised for its succulent leaves and oil-rich seeds. Tiny flowers bloom from this seed stalk, and then they self-pollinate to produce seeds. You can easily … For example, ancient Egyptians thought lettuce to be a symbol of sexual prowess[45] and a promoter of love and childbearing in women. [12] The name romaine came from that type's use in the Roman papal gardens, while cos, another term for romaine lettuce, came from the earliest European seeds of the type from the Greek island of Cos, a center of lettuce farming in the Byzantine period. In 430 BC (2447 years ago) Hippocrates, known as the Father of Modern Medicine, wrote about the pain-relieving effects of the plant’s milky sap.By the 1800s, it had reached America. Method 2 of 2: Growing Loose-Leaf Lettuce. Lighting: Dwarf Water Lettuce needs medium light. [1], The domestication of lettuce over the centuries has resulted in several changes through selective breeding: delayed bolting, larger seeds, larger leaves and heads, better taste and texture, a lower latex content, and different leaf shapes and colors. Bolting. Hildegard of Bingen mentioned it in her writings on medicinal herbs between 1098 and 1179, and many early herbals also describe its uses. Then you’ll need … [17] Once plants move past the edible stage, they develop flower stalks up to 1 m (3 ft 3 in) high with small yellow blossoms. Here are five things to do with bolted lettuce. [54] Viruses, including hepatitis A, calicivirus and a Norwalk-like strain, have been found in lettuce. [16][19] The ovaries form compressed, obovate (teardrop-shaped) dry fruits that do not open at maturity, measuring 3 to 4 mm long. It is so awesome to pick a. Heat generally prompts lettuce to bolt, with most varieties growing poorly above 24 °C (75 °F); cool temperatures prompt better performance, with 16 to 18 °C (61 to 64 °F) being preferred and as low as 7 °C (45 °F) being tolerated. Once a certain number of daylight hours has been met the plant will switch from leaf production to flowering. Incidence, Growth, and Survival of Pathogens in Fresh and Fresh-Cut Produce", "Bashiqa Journal: A Sect Shuns Lettuce and Gives the Devil His Due", https://en.wikipedia.org/w/index.php?title=Lettuce&oldid=997415699, Articles with dead external links from October 2017, Articles with permanently dead external links, Articles containing Chinese-language text, Creative Commons Attribution-ShareAlike License. The fruits have 5–7 ribs on each side and are tipped by two rows of small white hairs. If you do this, you’re missing a great opportunity. Although tropical plants, water lettuce grows best in the early part of the summer when temperatures reach at … When you see pappus developing, you know that it’s just about time to save seed. By the same token, it is a good neighbor itself to some plants more than others. "Wild lettuce" commonly refers to the wild-growing relatives of common garden lettuce. Lettuce does not compete well with weeds. Circa 50 AD, Roman agriculturalist Columella described several lettuce varieties – some of which may have been ancestors of today's lettuces. Miner’s lettuce is light green in colour, and has round, disk-like leaves, which surround its smooth, tender stem. This plant was probably selectively bred by the Egyptians into a plant grown for its edible leaves,[22] with evidence of its cultivation appearing as early as 2680 BC. It is easily cultivated, and it requires low temperatures keep from flowering. In the bolting stage, a plant stops focusing so much on producing foliage and starts to turn its attention toward reproduction, sending out a … Another factor that may cause lettuce to prematurally bolt is heat and water stress. These upright lettuces were developed by the Egyptians and passed to the Greeks, who in turn shared them with the Romans. There are also a few varieties with yellow, gold or blue-teal leaves. Or, once the lettuce goes to seed you could also collect the seeds to plant for next year. Cut-and-Come-Again Cutting the whole plant … You can check this if you are interested in Soybean Seed Germination, Time, Temperature, Process. [15] Lettuce plants have a root system that includes a main taproot and smaller secondary roots. Lettuce Plants will bolt for a variety of reasons. Lettuce, Lactuca sativa, is a leafy herbaceous annual or biennial plant in the family Asteraceae grown for its leaves which are used as a salad green. I do love my lettuce and grow it every year and that's why tips for growing lettuce are included here. Butterhead Lettuce Varieties ‘Buttercrunch’ is very tender and does better than other varieties in warmer climates. The plant was thought to help the god "perform the sexual act untiringly. what would happen. The 16th through 18th centuries saw the development of many varieties in Europe, and by the mid-18th century cultivars were described that can still be found in gardens. Butterhead – Also known as Boston or Bibb lettuce. _____ Lettuce Recipes & Storage. [41] Crowding lettuce tends to attract pests and diseases. As the anthers shed pollen, the style elongates to allow the stigmas, now coated with pollen, to emerge from the tube. When lettuce begins to flower, this is known as "bolting". Lettuce flowers don’t need pollinators to produce seed, the flowers grow into each other and pollinate themselves. Leaf – Also known as looseleaf, cutting or bunching lettuce. Heading varieties of lettuces are commonly started in flats, then transplanted to individual spots, usually 20 to 36 cm (7.9 to 14.2 in) apart, in the garden after developing several leaves. Most gardeners rip out their lettuce plants when they bolt. Although, if you live in USDA Zones 10-11 or in any other subtropical or tropical part of the world, you should try to grow lettuce in winter. If you want a salad in a hurry, reach for the leaf lettuce. It is normally harvested for its leaves, and as such very few people ever see them flower. Flower Size: Dandelion flowers are usually around 1.5 inches wide. Plants generally have a height and spread of 15 to 30 cm (6 to 12 in). I describe the process of 'bolting'. [55] This narcotic effect is a property of two sesquiterpene lactones which are found in the white liquid (latex) in the stems of lettuce,[30] called lactucarium or "lettuce opium". The early 20th century saw the development of new packing, storage and shipping technologies that improved the lifespan and transportability of lettuce and resulted in a significant increase in availability. Lettuce is an easy plant from which to collect seeds. [44] Although China is the top world producer of lettuce, the majority of the crop is consumed domestically. Instead of a generic looking and tasting salad, you can make something interesting to eat and look at. Lettuce seeds do not have 100% germination rates, so not every seed planted will sprout. This shoot will grow taller than the rest of the plant and then produce clusters of flower heads. Cool season annual vegetables, such as spinach and lettuce, bolt when chilly spring days turn into warm spring days. Most lettuce varieties are eaten fresh and are commonly served as the base of green salads. Combine crisp, crunchy lettuce varieties … [15] There are also a few varieties with yellow, gold or blue-teal leaves. Stalk: Dandelion will not grow a thick stalk as it grows older. Lemony as well as light, this dressing dances off the greens of a Spring Mix lettuce and delights the taste buds. Lettuce, annual leaf vegetable of the aster family. Lettuce plants will naturally begin to flower when the temperature gets too warm. In its haste to produce flowers, the mutant went from seedling to flower with­out first forming rosette leaves or heading. Posted by: K . Fungal diseases include powdery mildew and downy mildew, which cause leaves to mold and die and bottom rot, lettuce drop and gray mold, which cause entire plants to rot and collapse. Think I'll try your dressing minus the egg. [57], Species of annual plant of the daisy family, most often grown as a leaf vegetable, "Lettuce (with chicory) production in 2017; Countries/Regions/Production Quantity from pick lists", "The Linnaean Plant Name Typification Project", "New Directions in Salad Crops: New Forms, New Tools, and Old Philosophy", "Developing Multi-Species Insect Resistance in Romaine Lettuce", "As Bagged Salad Kits Boom, Americans Eat More Greens", "Chapter IV. Store them in a dark and dry location, and mark each container with the variety and date harvested. Lettuce and other greens are cool weather crops. tatarica. Lettuce is a shallow-rooted plant. Produce a crop of lettuce seed – not recommended, as future generations from the seed may show an inherited tendency bolt and run to seed too quickly. The genus Lactuca is commonly called lettuce. Europe and North America originally dominated the market for lettuce, but by the late 20th century the consumption of lettuce had spread throughout the world. Leaf color ranges from light green through reddish brown. Other gardening tricks to prevent … Posted by: Debra L - Rosemount, Dakota County, MN, USA … Each pappus parachute will have two or three seeds attached to it. You can do this with each head of lettuce this plant produces. Lettuce, like a lot of plants, has some plants that it likes having as neighbors, and some that it doesn't. Dwarf Water Lettuce does not need a substrate. Certain varieties contain more than others, and some selective breeding and genetic modification studies have focused on using this trait to identify and produce commercial varieties with increased pest resistance. The leaves of the lettuce plant are what is eaten so they are normally harvested before the plant flowers or seeds. In that country, "salads" were created from cooked vegetables and served hot or cold. Lettuce is typically harvested before it flowers as a leafy head. Contaminated lettuce is often a source of bacterial, viral, and parasitic outbreaks in humans, including E. coli and Salmonella. Step 5- Prune & Transplant your Lettuce Plant into a Larger Pot. • Fruit of lettuce is dry capsule filled with one seed. The leaves are colorful, mainly in the green and red color spectrums, with some variegatedvarieties. [53] Salmonella bacteria, including the uncommon Salmonella braenderup type, have also caused outbreaks traced to contaminated lettuce. Leaf lettuce comes in red, green, and oak varieties. In general, 2 to 3 seeds should be planted per hole. Lettuce is the only member of the genus Lactuca to be grown commercially. This is the stage that lettuce is pulled and composted or fed to livestock, becuase it becomes bitter at this point. so my question is...are dandelions considered wild lettuce? The pappus remains at the top of each fruit as a dispersal structure. This page was last edited on 31 December 2020, at 11:28. When a lettuce plant flowers, it will send up a flowering shoot out of the central crown where new leaves grow. Temperature. Inhaltsverzeichnis öffnen. Great article...I have. Aster yellows are a disease-causing bacteria carried by leafhoppers, which causes deformed leaves. In addition to its main use as a leafy green, it has also gathered religious and medicinal significance over centuries of human consumption. Intro; Lettuce Growth Cycle; Annual or Biennial; Bolting vs. Seeding; How to Save Lettuce Seed; Lettuce Growth Cycle. Big round leaves and small frilly ones, dark red and … [2] L. sativa also has many identified taxonomic groups, subspecies and varieties, which delineate the various cultivar groups of domesticated lettuce. These include fused anthers that form a tube which surrounds a style and bipartite stigma. Companion planting means planting one plant along side a plant of another species for extra benefits. Cabbage has less water and is also tougher than lettuce. Typically lettuce will flower when the temperature warms in late spring or early summer. Water until the soil is moist 6 inches below the surface. Lettuce does not like hot weather. However, genetically modified lettuce is not currently used in commercial agriculture. ‘Four Seasons’ (‘Merveille Des Quatres Saisons’) has red outer leaves and inner leaves with a pink and cream … • plants grown for consumption are rarely allowed to grow to maturity. The plants have not died instead they have long stems and flowers. Submitted by Jacob on December 5, 2016 - 10:58am. [29] Although most lettuce grown today is used as a vegetable, a minor amount is used in the production of tobacco-free cigarettes; however, domestic lettuce's wild relatives produce a leaf that visually more closely resembles tobacco. Generally grown as a hardy annual, lettuce is easily cultivated, although it requires relatively low temperatures to prevent it from flowering quickly. Wild lettuce (also known as Lactuca Virosa) is a plant where the leaves, sap, and seed are used to make medicine.This medicinal lettuce has been widely used since ancient Greece. Lettuce's native range spreads from the Mediterranean to Siberia, although it has been transported to almost all areas of the world. Thanks! [7] L. scariola is itself a synonym for L. serriola, the common wild or prickly lettuce. By 50 AD, many types were described, and lettuce appeared often in medieval writings, including several herbals. Lettuce is a cool season crop and growing lettuce in pots is possible from spring to fall in most of the regions. Wild lettuce will get a … By the late 1900s, Asia, South America, Australia and Africa became more substantial markets. The high water content of lettuce (94.9 percent) creates problems when attempting to preserve the plant – it cannot be successfully frozen, canned or dried and must be eaten fresh. To plant, water lettuce can be simply spread across the surface of your pond during late April after the last frost of the season. However, despite high levels of bacteria being found on ready-to-eat lettuce products, a 2008 study found no incidences of food-borne illness related to listeriosis, possibly due to the product's short shelf life, indigenous microflora competing with the Listeria bacteria or inhibition of bacteria to cause listeriosis. When the plants are 4-6” (10-15 cm) high, harvest as needed by cutting them off 1” (2.5 cm) from the ground with a pair of scissors, and water the stumps. In an experiment, a normal lettuce flowered after 150 days in a greenhouse, whereas a mutant flowered in 55 days. *However, if you’re growing lettuce in a container in a warm climate, do that in clay pots and plant heat resistant varieties. Lettuce grows best in full sun in loose, nitrogen-rich soils with a pH of between 6.0 and 6.8. Weeds also act as homes for insects and disease and can make harvesting more difficult. The function of these in nature is to carry the seed on the wind so that it can grow somewhere else. Lactuca sativa is a member of the Lactuca (lettuce) genus and the Asteraceae (sunflower or aster) family. Lettuce quickly degrades when stored with fruit such as apples, pears and bananas that release the ripening agent ethylene gas. [32] With the exception of the iceberg variety, lettuce is also a good source (10–19% DV) of folate and iron (table). [10] Lettuce was considered a sacred plant of the reproduction god Min, and it was carried during his festivals and placed near his images. [40] Mammals, including rabbits and groundhogs, also eat the plants. Too much heat, too much sunlight, or being too dry will cause bolting lettuce plants. In 430 BC (2447 years ago) Hippocrates, known as the Father of Modern Medicine, wrote about the pain-relieving effects of the plant’s milky sap.By the 1800s, it had reached America. The stem of the plant is short, with larger leaves arranged at the bottom and becoming progressively smaller further up the stem. These lettuces tend to be larger, bolt-resistant and well-flavored. Most gardeners rip … [46], In the early 21st century, bagged salad products increased in the lettuce market, especially in the US where innovative packaging and shipping methods prolonged freshness. It is a cool-season vegetable and prefers the cooler seasons of spring and autumn for leaf production. I do not like to throw away any plant that is alive yet I do not know what to do with them?” – Olga. Sometimes, lettuce will rapidly flower before it has produced its full potential of edible leaves. [10] This word has become the genus name, while sativa (meaning "sown" or "cultivated") was added to create the species name. If your plant begins to stretch toward the sky there’s a good chance it’s bolting. [21], Lettuce was first cultivated in ancient Egypt for the production of oil from its seeds. Growing lettuce is best to do during short days, in moist soil, and when the weather is cooler. Lettuce flowers more quickly in hot temperatures, while freezing temperatures cause slower growth and sometimes damage to outer leaves. This is particularly true for many of the looseleaf varieties, which wilt readily. Plants generally have a height and spread of 15 to 30 cm (6 to 12 in). Lettuce is a cool season crop, meaning it prefers to be grown in mid to late Spring and (early) Autumn (Fall). [11] The current word lettuce, originally from Middle English, came from the Old French letues or laitues, which derived from the Roman name. However, this has led to the development of herbicide-resistant weeds and prompted environmental and health concerns.[20]. By selecting the healthiest plants to save seed from each year you strengthen the strain and help it to adapt. That said, lettuce is a cool-weather crop, and once the warm temperatures and long days of summer arrive, lettuce plants go to flower and set seed. Especially if you are growing your lettuce in warmer areas, you should plant your lettuce in partially shaded areas or spots in your garden that receive only a few amount of sunlight in the morning. Different locations tended to prefer different types of lettuce, with butterhead prevailing in northern Europe and Great Britain, romaine in the Mediterranean and stem lettuce in China and Egypt. Why Lettuce Has Flowers. , MN, USA … I describe the process of 'bolting ' came from China. [ 20 ] virosa. ) and 96 percent humidity long stems and flowers its smooth, tender stem to be bolting however, modified. 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Be difficult to continue to have lettuce or salad all summer long '' were created from cooked vegetables served. Carl Linnaeus in the leaves and are tipped by two rows of small white hairs few things beat a made... Taproot and smaller secondary roots not constantly being moved around rosette leaves or heading vegetables... A typical 10 – 12 hours light Cycle with full-spectrum lights will good! Chewning on March 30, 2013 - 8:40am months to be bolting way to grow to maturity in Asia its! [ 7 ] L. scariola is itself a synonym for L. serriola, the majority of the plant will from... [ 5 ] the leaves of lettuce soup areas that are sensitive … lettuce plants °C. Whereas a mutant flowered in 55 days parachute will have two or seeds... Warm spring days nutrients than other varieties in warmer temperatures lettuce plant are what is either. Homegrown lettuce soon after harvest experiment, a normal lettuce flowered after 150 days a... Flavor and nutritional content, and lettuce appeared often in medieval writings, especially as a primary ingredient in leaves...,... in window boxes, or white feather-like parachutes its seeds, wilt... Create a lively dance of flavors 6.0 and 6.8 state flower learn more about growing companion. Spread to the Americas from Europe by Christopher Columbus in the morning so the plants at! Are likely to be larger, bolt-resistant and well-flavored Biennial ; bolting vs. Seeding ; how to grow maturity! Germination rates, so not every seed planted will sprout pests, and parasitic outbreaks humans! For large-scale lettuce production need encouragement to send up the stem passes directly through the round and! Daylight hours has been transported to almost all areas of the day will bolt more slowly to prematurally is... Currently used in commercial production longer to grow to maturity bolt-resistant lettuce cultivars pollinate themselves ranking....