Citrons

Citron
Some 16 species of small, evergreen trees and shrubs comprise this genus, native to SE Asia and E Pacific islands. Most citruses have been cultivated for so long that their origins are obscure. The species are very closely related, with numerous hybrids and cultivars. Citruses were unknown in Europe in Classical times, through C. aurantium and C. bergamia were first mentioned in Chinese medicine in the first century CE. The first citrus to arrive in Europe was the bitter orange, C. aurantium, probably brought by the Portuguese from the East Indies. It was followed by C. limon, probably from China, somewhere between tthe 11th and 13th centuries. Medicinal uses of citruses are complex. Various parts of the tree are used, and also various parts of the fruit at different stages of ripeness. Commonly, the leaves, fruits, juice and bark are used, while in China several quite different drugs are prepared from the fruits alone - one of the most valuable being the peel of C. reticulata, which becomes more potent with age. The related Poncirus trifoliata (hardy orange, Japanese bitter orange) is used in identical ways to C. aurantium. Citruses are high in vitamin C, flavonoids, acids, and volatile oils. They also contain coumarins, such as bergapten, which sensitize the skin to sunlight. Bergapten is sometimes added to tanning preparations and may cause dermatitis or allergic responses. The most recent uses of citruses are anti-oxidants and chemical exfoliants in cosmetics.

Large shrub or small, spiny tree with elliptic-ovate, toothed leaves, 10-18cm (4-7in) long. White purple-flushed flowers, 4cm (1½in) wide, appear in spring and summer, followed by ovoid-oblong, yellow fruits, to 30cm (12in) long.

Common Name:	Citron
Botanical Name:	Citrus medica
Genus:	Citrus
Family:	Rutacea
Native Location:	SW Asia
Cultivation:	Well-drained, neutral to slightly acid soil in sun, with ample moisture during the growing season. Scale insects, mealybugs, and tortrix moth caterpillars may affect plants under cover. Citruses do not transplant well.
Propagation:	By seed sown when ripe or in spring at 16° C (61°F); by semi-ripe cuttings in summer. Cultivars do not come true from seed.
Harvest:	Flowers (C. aurantium, C. bergamia) are picked when first open and distilled for oil. Leaves (C. aurantiifolia, C. hystrix) are picked as required for flavoring and infusions. Oil is distilled from foliage, unripe fruits (C. aurantium) and ripe fruits (C. bergamia). Fruits are picked when unripe or ripe for culinary use, candying, or oil distillation, and either unripe or ripe (C. aurantium, C. reticulata) for use in Chinese medicine.
Variations:	Etrog Is smaller and less vigorous, with thick-skinned, highly aromatic fruits. 15-25cm (6-10in) long, excellent for candying. Var. digitata syn. var. sarcodactylis (Buddha's hand/fingers) Has strange fruits, wholly or partly divided into finger-like sections, lacking pulp and often seedless. Popular as offering in Buddhist temples, for scenting rooms and clothing.
Height:	3-5m (10-15ft)
Width:	2-3m (6-10ft)
Hardiness:	Min.3-5°C (37-41°F). Sometimes withstands short periods of 0°C (32°F)
Parts Used:	Fruits, peel
Properties:	A highly aromatic herb.
Culinary Uses:	Fruits of 'Etrog' variety are eaten during the Jewish Feast of the Tabernacles. Peel is candied or used in making candy.
Bibliography:	Encyclopedia of Herbs by Deni Brown Copyright © 1995, 2001 Dorling Kindersley Limited Pp 171-173