Lime - Citrus aurantifolia

The Lime tree or Lime, in Latin Citrus aurantiifolia, is a moderately vigorous citrus tree, with a well-branched and ornamental habit, and highly floriferous in spring. Its small white star-shaped flowers, pleasantly scented, are followed by small fruits that are more or less spherical, covered with a smooth and thin skin, very fragrant when still dark green. The flesh of this citrus fruit is very juicy, particularly acidic but highly aromatic. This species, the least hardy of all citrus trees, has marked tropical requirements: it perishes below -3°C (26.6°F) and requires warmth throughout the year to fruit well. It can be grown in a large container and stored in a slightly heated greenhouse during winter, or planted in open ground in warm regions that are spared from frost.

Citrus aurantifolia is a spiny bush from the Rutaceae family, with a rather upright and bushy habit. It is believed to be originally from Southeast Asia, specifically from Malaysia and the Philippines, although its exact origin is a bit unclear. Recent studies tend to prove a hybrid origin between Citrus medica (citron) and C. micrantha (wild Philippine lime).

This small tree reaches a height of 3.50m (11ft) and spreads over approximately 2.50m (8ft). Its branches are short and carry numerous short and sharp thorns. Not very hardy, it can be planted in open ground along the narrow coastal strip of the Mediterranean. Elsewhere, it should be grown in a pot and stored at the first signs of cold weather. Primarily cultivated for its fruits, the lime tree blooms abundantly in March-April, and then sporadically until autumn in Mediterranean climates. It produces small white flowers, slightly tinged with yellow at the center, and with a sweet and delicious neroli fragrance, characteristic of citrus. These flowers give way to oval to rounded fruits, resembling yellow lemons, with a diameter of 3 to 5cm (1 to 2in). The very thin and smooth skin of the fruit is initially dark green and then turns green-yellow. The flesh of the fruit, white-green and translucent, is both very juicy and very acidic, and contains a few seeds. The fruits are harvested while still green, when their concentration of essential oils is at its peak. The evergreen and aromatic leaves of this citrus tree are ovate, leathery, small in size, and intensely green in colour.

The fruits are part of the culinary traditions of several countries in Southeast Asia, as well as Reunion Island and the Caribbean. Its use is almost as extensive as that of yellow lemons, in savory or sweet dishes. Its juice is used in refreshing drinks or cocktails, adding a touch of acidity and a unique aroma. The zest is sometimes used to flavour pastries. Combined with a little chili, lime is often served with Reunionese dishes and Caribbean ti-punch. In addition to its culinary importance, the lime tree is also a medicinal plant whose therapeutic properties, used for centuries in traditional medicine, are now the subject of in-depth scientific research. Lime is less rich than lemon in ascorbic acid (Vitamin C), as well as in vitamins A and B. Easy to store, this citrus fruit was once loaded onto sailing ships, providing a good source of vitamins to fight against scurvy.

Like all Citrus, the lime tree contains visible essential oil sacs in its leaves, flowers, and fruits, which are extracted by distillation (flower and leaves) or by pressing (zest). The essential oil has rebalancing properties and is slightly sedative, helping to centre vital energies. Stimulating, the essential oil is known to facilitate blood circulation. The fragrance of the essential oil is described as fresh, lemony, tangy, with slightly sweet and bitter notes.

Most citrus trees thrive in open ground in Mediterranean coastal regions, where they find the necessary warmth all year round. To fruit well, they must not lack water or nutrients. Not very hardy, the Citrus aurantifolia starts to suffer from cold temperatures below 0°C (32°F). It is a self-fertile bush, which means that a single individual is sufficient for complete pollination and fruiting.