Lemon Tree - Citrus limon

Common Names: Lemon, lemon tree, citrus, limone, limón, citronnier, citroen, French lemon, yellow lemon, lamoentsji, lamunchi, rough lemon, sweet lemon, Meyer lemon, Perrine lemon, Ponderosa lemon, Citrus limon

Latin Name: Citrus limonum (limon)

Origin: Asia, Europe, South America, North America

Short Introduction

Lemons require temperatures above 7°C for optimal growth and are therefore not suitable for year-round outdoor cultivation in temperate zones. In countries like the Czech Republic, lemon trees are grown in greenhouses or indoors, ideally overwintered in cool (5–15°C) conditions. Early flowering is achieved with grafted or cutting-propagated plants. For robust branching, regular pruning is advised. Citrus trees bloom several times per year, often irregularly—mature fruit, immature fruit, and blossoms may appear simultaneously on a single plant. In 2014, global lemon production exceeded 16 million tons, with top producers including India, Mexico, China, Cyprus, Lebanon, Turkey, Greece, Italy, Spain, Australia, the Philippines, and several South American countries (such as Argentina, Brazil, and Guatemala). Lemon trees require very rich, fertile, sandy soils with high permeability and a pH between 5.5 and 6.5.

Detailed Description

It's no coincidence the saying goes "as sour as a lemon." According to old British tradition, a well-bred Englishman is said to always look as though they're biting into a lemon.

Botanical Information

The lemon is the fruit of the lemon tree. The fruit is a type of hesperidium, typically egg-shaped, with a sour taste, ranging in color from dark green and light green to yellow, and about the size of an egg (3–6 cm). The lemon tree is a small, evergreen tree, usually reaching 3–6 meters in height, with irregular branches and sharp thorns at the tips. The alternate leaves are elliptic to heart-shaped, 5–8 cm long, green, toothed along the edges, and pointed at the tip. The buds are reddish. The white blossoms are about 2 cm wide with a slight pink tint to the petals.

Origin and Distribution

The lemon tree originates from the subtropical regions of Southeast Asia, most likely from what is now northwestern India. Today, it is commercially cultivated in India, China, throughout Southern and East Asia, Mexico, South America, and in Europe around the Mediterranean (with Italy as a leading producer). Lemons are believed to have been introduced to Europe around 200 AD from what is now Iraq, Syria, and Egypt. By the late 18th century, cultivation had spread to California and Florida. Lemon trees can be grown in temperate climates—such as in the Czech Republic—if conditions are controlled (indoor temperature, sunny and sheltered balconies, greenhouses, etc.).

Usage / Dosage

Historically, the lemon tree was an important natural source for the production of citric acid. Today, lemons are widely used in both culinary and cleaning applications. The aromatic compounds found in lemons are key to its use in cooking and baking (cakes, pastries, desserts, cookies, puddings, sorbets, candies, confections, and in combination with sugar), as well as in beverages like lemonade. Lemon juice or grated lemon zest is used in many cultures to flavor fish, poultry, veal, and ham. Lemon is also added to bread, rolls, and a variety of canned foods and pharmaceutical products.

For cleaning purposes, the lemon tree was traditionally valued as a natural disinfectant. Lemon combined with salt and baking soda is used for cleaning copper cookware. Home enthusiasts use various parts of the lemon with baking soda to remove stains from plastic food containers. The citric acid in lemon easily dissolves stains and aids in cleaning. Lemon juice neutralizes odors, removes grease, whitens some stains, and disinfects surfaces. Other parts of the tree are used as cleaning agents or wood polish, and as a natural insecticide.

Lemon's compounds show notable effects on the human body. Its essential oil is said to help relieve constipation, slow the progression of ulcers along the digestive tract, and reduce gastric acidity. Consuming lemon between meals, accompanied by sufficient water, may alleviate bloating and fullness, and in some cases reduce nausea and vomiting.

Due to its high Vitamin C content, lemon is given in cases of liver diseases and symptoms of jaundice, and in some countries it's still recommended in high doses for this purpose. Vitamin C and caffeine content may help relieve acute pain and play a role in preventing chronic pain conditions such as migraine. Similar effects are observed with regular tea, cocoa, and coffee consumption. Lemon compounds are also believed to support falling asleep and provide a relaxing effect on the central nervous system.

Vitamin C and limonene have demonstrated some benefit (as adjunct treatment) in alleviating the symptoms of rheumatism, gout, arthritic disorders, high uric acid, and degenerative inflammatory diseases of the musculoskeletal system. The essential oil found in almost every part of the lemon tree helps improve both inflammatory and non-inflammatory conditions of the musculoskeletal system. Lemon's oil compounds are also used in aromatherapy, where they are valued for calming and relaxing effects.

Traditional and Folk Uses

According to folk medicine, lemon juice or grated lemon zest is traditionally used for refreshment, energy boost, mood improvement, and as a source of creativity—especially during times of low inspiration or motivation. It is also recommended for lack of motivation toward work, apathy, the early stages of depression, and fatigue. Herbalists and folk healers attribute to lemon tree antiseptic, diuretic, and perspiration-inducing properties, as well as benefits for reducing bloating, lowering high blood pressure, reducing cramps, and fever relief.

Active Compounds

Different parts of the lemon fruit contain high levels of ascorbic acid (Vitamin C), caffeic acid, malic acid, and citric acid (about 3–8 g per 100 g of fruit), as well as approximately 85% water. These acids give lemon parts their distinctive sour pH. Other important compounds include flavonoids (hesperidoside, limocitrin), essential oils (isopulegol, bergamotene, alpha-pinene, alpha-terpinene, terpineol, camphene, alpha-thujene, bisabolene, phellandrene, citral, citronellal, limonene, sabinene), coumarins, carotenoids, mucilage, oxalates, caffeine, provitamin A and B, carbohydrates, pectin, and minerals (calcium, potassium, phosphorus, zinc, iron, magnesium).

Traditional Dosage

Lemon peel is used as a powder in both sweet and savory baked goods and cooked dishes. The peel itself (2–12 g) may be simmered for 5–10 minutes along with other parts of the tree or with sugar, and the resulting solution (300–500 ml per serving) is consumed 2–3 times daily. The same decoction can be applied externally to affected skin 2–3 times per day. Lemon peel can also be gently simmered in milk.