901 Camellia sinensisCommon Names: tea, tea plant, tea tree Family: Theaceae (tea Family)
The source of the world's most popular caffeine drink, the tea plant is an evergreen shrub or small tree with glossy dark green elliptic leaves. Var. sinensis, the most widely grown variety, gets 5-10 ft (1.5-3.1 m) tall, and has leaves 1-3 in (2.5-7.6 cm) long and 1-2 in (2.5-5.1 cm) wide. Var. assamica (Assam or wild tea) can get up to 50 ft (15.2 m) tall and has larger leaves, 6-10 in (15.2-25.4 cm) long and 3-5 in (7.6-12.7 cm) wide. Tea plants bloom in the autumn with fragrant, nodding cup shaped flowers about 1 in (2.5 cm) wide. The seven or eight petals are white. In commercial tea plantations the plants are kept pruned to about 4 ft (1.2 m) tall and flowers are rarely produced.
The typical variety (var. sinensis) is probably native to western China. It has been cultivated for centuries, mostly in plantations in China and at high elevations in tropical southern Asia. More recently it is being cultivated in other areas of the world with suitable mild and humid climates. Assam tea (var. assamica) occurs naturally in tropical and subtropical southeastern Asia and is cultivated extensively in India and Sri Lanka.
CultureLight: Seedlings and young tea plants should be shaded; mature plants produce best in full sun. Moisture: Tea plants need plenty of moisture. They do best in rather humid climates. Hardiness: USDA Zones 9 - 11. Tea plants do best in a cool, but frost-free climate. They can, however, withstand light freezes when dormant. Propagation: Tea plants are propagated by rooting semiripe cuttings, and by budding, grafting, and air layering. Teas are sometimes grown from seed as well.
The tender young leaves from tea plants are plucked and variously "fermented" (actually oxidized - no yeast or microbes are involved), then dried to make green, black or oolong teas. Green tea is made from fresh leaves that are steamed and wilted, then dried immediately. Black tea is made from leaves that are wilted and crushed in rollers, then allowed to oxidize for several hours before they are dried. Oolong tea comes from leaves that are only partially oxidized before drying. Black teas are graded by the size of the particles. This is important since larger pieces take longer to brew. The Pekoe teas are supposedly the highest quality black teas, made from the youngest, "first flush" of leaves. Orange Pekoe is the best, made into long, thin, twisted leaves; regular Pekoe tea leaves are more open. Souchong teas are black teas with larger open, coarse leaves. In India they mostly make black teas, including the full-bodied Assam tea and the delicate Darjeeling, sometimes called the "champagne of teas." Green teas are graded based on the age of the leaves and the method of preparation. Gunpowder teas consist of little tightly rolled balls of young leaves; they produce a pale-colored green tea known for its sharp, distinctive flavor. Imperial is like Gunpowder but with larger, looser pieces of leaf. Earl Grey is a black tea flavored with oil of bergamot (a type of sour orange, Citrus aurantium). Teas are sometimes flavored with jasmine flowers (see Arabian jasmine), orange blossoms (Citrus sinensis), rose petals, apples or mangos. In addition to its nearly universal popularity as a beverage, tea also is used as a flavoring in various foods, including ice cream, and fish and meat dishes.
Tea (the beverage - not the plant) was introduced into Europe in the middle 16th century. By the 1700's it began to replace beer as the beverage of choice at breakfast.
Research has shown that tea contains components that inhibit tooth decay. Decoctions of green tea aid digestion and help to ward off cancers. It has been shown that people who drink at least one cup of tea a day have a lower risk of heart disease, stroke and cancer. Brewed tea contains large quantities of antioxidants - more in fact than any other fruit or vegetable.
The antioxidants in tea (various polyphenols) are more effective at neutralizing damaging free radicals than those in other foods. (Free radicals are highly unstable molecules produced in the body by normal metabolism and by exposure to radiation, chemicals and heavy metals; free radicals damage cells, proteins and fats in the body, theoretically causing a wide range of diseases including even the aging process.)
Decaffeinated tea has just as much antioxidant activity as normal tea, and adding milk, lemon juice or sugar does not reduce the antioxidant effects either. Powdered instant teas and bottled iced teas do contain fewer antioxidants than brewed tea, but still more than most individual fruits and vegetables. Many studies have demonstrated that green tea, either consumed internally or applied directly to the body, can protect lab animals against breast, colon, skin, liver, stomach, pancreas and esophagus cancers. It appears that tea can kill or slow the growth of cancer cells while leaving normal cells unscathed. Green teas have been studied the most, but black and oolong teas may be just as effective. To get the most benefit, steep tea bags for a full five minutes in boiled water.
Steve Christman 01/15/01; updated 12/1/03, 1/25/04