- Lemon seedling
Full-sized tree- Flower
- Lemon with leaves
- Lemon cidra
- Mature lemons
- Variegated pink lemon
The lemon (Citrus × limon) is a species of small evergreen tree in the flowering plant family Rutaceae, native to Asia, primarily Northeast India (Assam), Northern Myanmar, and China.[2]
The tree's ellipsoidal yellow fruit is used for culinary and non-culinary purposes throughout the world, primarily for its juice, which has both culinary and cleaning uses.[2] The pulp and rind are also used in cooking and baking. The juice of the lemon is about 5–6% citric acid,[3] with a pH of around 2.2,[4] giving it a sour taste. The distinctive sour taste of lemon juice, derived from the citric acid, makes it a key ingredient in drinks and foods[5] such as lemonade and lemon meringue pie.
The lemon tree produces an ellipsoidal yellow fruit.
Lemons contain numerous phytochemicals, including polyphenols, terpenes, and tannins.[6] Lemon juice contains slightly more citric acid than lime juice (about 47 g/L), nearly twice the citric acid of grapefruit juice, and about five times the amount of citric acid found in orange juice.[3]
The origin of the lemon is unknown, though lemons are thought to have first grown in northeast India.[2] A genomic study of the lemon indicated it was a hybrid between bitter orange (sour orange) and citron.[7][8]
The origin of the word lemon may be Middle Eastern.[2] The word draws from the Old French limon, then Italian limone, from the Arabic laymūn or līmūn, and from the Persian līmūn, a generic term for citrus fruit, which is a cognate of Sanskrit (nimbū, 'lime').[9]
The 'Bonnie Brae' is oblong, smooth, thin-skinned, and seedless.[10] These are mostly grown in San Diego County, US.[11]
The 'Eureka' grows year-round and abundantly. This is the common supermarket lemon, also known as "Four Seasons" (Quatre Saisons) because of its ability to produce fruit and flowers together throughout the year. This variety is also available as a plant for domestic customers.[12] There is also a pink-fleshed Eureka lemon with a green and yellow variegated outer skin.[13]
The Lisbon lemon is very similar to the Eureka and is the other common supermarket lemon. It is smoother than the Eureka, has thinner skin, and has fewer or no seeds. It generally produces more juice than the Eureka.[14][15]
The 'Femminello St. Teresa', or 'Sorrento'[16] originates in Italy. This fruit's zest is high in lemon oils. It is the variety traditionally used in the making of limoncello.
The 'Yen Ben' is an Australasian cultivar.[17]
Lemons are supposed to have entered Europe near southern Italy no later than the second century AD, during the time of Ancient Rome.[2] They were later introduced to Persia and then to Iraq and Egypt around 700 AD.[2] The lemon was first recorded in literature in a 10th-century Arabic treatise on farming and was also used as an ornamental plant in early Islamic gardens.[2] It was distributed widely throughout the Arab world and the Mediterranean region between 1000 and 1150.[2] An article on Lemon and lime tree cultivation in Andalusia, Spain, is brought down in Ibn al-'Awwam's 12th-century agricultural work, Book on Agriculture.[18]
The first substantial cultivation of lemons in Europe began in Genoa in the middle of the 15th century. The lemon was later introduced to the Americas in 1493, when Christopher Columbus brought lemon seeds to Hispaniola on his voyages. Spanish conquest throughout the New World helped spread lemon seeds. It was mainly used as an ornamental plant and for medicine.[2] In the 19th century, lemons were increasingly planted in Florida and California.[2]
In 1747, James Lind's experiments on seamen suffering from scurvy involved adding lemon juice to their diets, though vitamin C was not yet known as an important dietary ingredient.[2][19]
Lemons need a minimum temperature of around 7 °C (45 °F), so they are not hardy year-round in temperate climates, but become hardier as they mature.[21] Citrus require minimal pruning by trimming overcrowded branches, with the tallest branch cut back to encourage bushy growth.[21] Throughout summer, pinching back tips of the most vigorous growth assures more abundant canopy development. As mature plants may produce unwanted, fast-growing shoots (called "water shoots"), these are removed from the main branches at the bottom or middle of the plant.[21]
There is reputed merit in the tradition of urinating near a lemon tree.[22][23]
In cultivation in the UK, the cultivars "Meyer"[24]and "Variegata"[25]have gained the Royal Horticultural Society's Award of Garden Merit (confirmed 2017).[26]
In 2022, world production of lemons (combined with limes for reporting) was 22 million tonnes led by India with 18% of the total. Mexico and China were major secondary producers (table).
