Family: Rutaceae
Common Name: Citrus Lemon

Thought to have originated in India, Citrus limon was relatively late to cultivation when compared with many other plants. Around the 12th century it was introduced to Spain by the Arabs and from there it was carried through the Mediterranean and eventually to most tropical and subtropical regions. Although attractive in appearance, with fragrant, white flowers, it is grown chiefly for its acid, juicy fruit. The juice is high in vitamin C, and often used to treat colds. It makes a delicious, refreshing drink. Lemon juice is used in salad dressings, cakes, icings and biscuits, and is mandatory with fish. A commercial oil is extracted from the rind, while citric acid is produced from the pulp. Lemon can also be used to remove rust or ink stains, and is an ingredient in perfumes, cos­metics and furniture polish.

Species

C. limon is a small, evergreen tree, with short spines, which grows to around 4-5 m (13-16 ft). It has oblong, leathery, deep green leaves, pointed at the end, and fragrant, waxy, white flowers. The fruit is oval to oblong in shape, with finely pitted rind. Cultivar 'Eureka' is an almost spineless tree with rounded or sharply pointed, dark green leaves, and is almost continuously in fruit. 'Lisbon' is a more upright tree, with lighter green leaves.

C. x meyeri 'Meyer', known as Meyer's lemon, is thought to be a hybrid of C. limon and C. sinensis. It is the hardiest lemon available, of compact habit, and has rounded, smooth, thin-skinned fruits. The fruits are very juicy and less acid than those of 'Eureka'.

Cultivation

In areas prone to hard frosts, grow in pots or tubs in an airy, cool to intermediate greenhouse or conservatory. Use soil-based pot­ting compost, and provide maximum light, but shade from strong sun. Outside, the lemon tree does best in a mild to warm climate. Plant in any reasonable, well-drained garden soil, in full sun. Keep the area free of weeds or long grass, and feed regularly with animal manure or chemical fertilizer. The lemon is usually grafted onto an understock resistant to disease.
Remove shoots below the graft. Little pruning is required. The fruit is produced on the previ­ous year's wood. If branches are weak or too long, cut them back. Lemons are ready for use when yellow; if they are to be stored, pick as soon as they start to change colour, usually in winter. Retain the swollen end of the stem and store in a cool, dark, well-ventilated place. Lemons keep better than other citrus fruit.

Climate

Zone 10 and warmer parts of zone 9.