Lemon

The lemon (Citrus × limon) is a hybrid citrus tree of cultivated origin. The fruit are used

primarily for their juice, though the pulp and rind (zest) are also used, primarily in cooking or

mixing. Lemon juice is about 5% citric acid, which gives lemons a sour taste and a pH of 2 to 3.

This acidity makes lemon juice a cheap, readily available acid for use in educational chemistry

experiments.

A lemon tree can grow up to 6 m (20 ft), but they are usually smaller. The branches are

thorny, and form an open crown. The leaves are green, shiny and elliptical-acuminate. Flowers are

white on the outside with a violet streaked interior. On a lemon tree, flowers and ripe fruits can

be found at the same time.

There are several varieties of lemon including Eureka, Lisbon and the Meyer lemon, which is

thought to be a hybrid.

Lemons grow in tropical and sub-tropical climates and cannot withstand frosts and very cold

temperatures. Their favored temperature is between 15–30 °C (60–85 °F). They thrive in

fertile soils and ample quantities of sunlight. Propagation is often by grafting as the stock is

vulnerable to cankers and dry rot.

Lemons are grown commercially in Spain, Portugal and other Mediterranean countries,

Argentina, Brazil and the United States. They can be grown as plants in the garden as well as in

containers if they are pruned to keep a small form.

The lemon is a cultivated hybrid deriving from wild species such as the citron and mandarin.

When and where this first occurred is not known. The citron, apparently the fruit described in

Pliny's Natural History (XII, vii.15) as the malum medicum — the "medicinal fruit" — seems to

have been the first citrus fruit known in the Mediterranean world. Depictions of citrus trees

appear in Roman mosaics of North Africa, but the first unequivocal description of the lemon, is

found in the early tenth-century Arabic treatise on farming by Qustus al-Rumi. At the end of the

twelfth century, Ibn Jami’, personal physician to the great Muslim leader Saladin, wrote a

treatise on the lemon, after which it is mentioned with greater frequency in the Mediterranean.

However, it is believed that the first lemons were originally cultivated in the hot, semi-arid

Deccan Plateau in Central India.

The origin of the name "lemon" is through Persian (لیمو Limu), akin to the Sanskrit

nimbuka. They were cultivated in Genoa in the mid-fifteenth century, and appeared in the Azores in

1494. More recent research has identified lemons in the ruins of Pompeii. Lemons were once used by

the British Royal navy to combat scurvy, as they provided a large amount of vitamin C.

Both lemons and limes are regularly served as lemonade or limeade, its equivalent, or as a

garnish for drinks such as iced tea or a soft drink, with a slice either inside or on the rim of

the glass. Only lemons, however, are used in the Italian liqueur Limoncello. A wedge of lemon is

also often used to add flavor to water.