The calamondin [x Citrofortunella mitis (Blanco) J. W. Ingram & H. E. Moore] is one of the natural citrus hybrid variety. They are usually referred to as C. mitis or C. microcarpa or sometimes referred to as C. madurensis, but this is incorrect as C. madurensis actually refers to F. japonica (Swingle, 1943; Wijnands, 1984). Ingram and Moore (1975) and Wijnands (1984) recognized the hybrid nature of this taxon with the coinages x Citrofortunella mitis and x Citrofortunella microcarpa, respectively. Additionally, its alternate common names are: calamondin orange (China), calamansi, kalamondin (Philippines), limau kesturi, limau chuit (Malayan), ma-nao-wan (Thailand).
The native place of calamondin is believed to be China and thought to have been taken in early times to Indonesia and the Philippines; also it is widely grown in India and throughout southern Asia and Malaysia. Moreover, it is a common ornamental dooryard tree in Hawaii, the Bahamas, some islands of the West Indies, and parts of Central America and also it is much utilized for greenhouse research on the various aspects of flowering and fruiting in citrus at Agricultural Experiment Station of the University of Florida in Gainesville.
The calamondin tree, ranging from 2.0 to 7.5 m high, is erect, often quite cylindrical, densely branched beginning close to the ground, slightly thorny, develops an extraordinarily deep taproot and grows well in tropical climates up to an elevation of 1,000 meters above sea level (Patena et al., 2005). The evergreen leaves are alternate, aromatic, broad-oval, dark-green, glossy on the upper surface, yellowish-green beneath, 4.0 to 7.5 cm long, faintly toothed at the apex, with short, narrowly-winged petioles. The richly and sweetly fragrant flowers, having 5 elliptic-oblong, pure-white petals, are about 2.5 cm wide and borne singly or in 2's or 3's terminally or in the leaf axils near the branch tips. The fruits are round or oblate and nearly 4.5 cm wide, with very aromatic, orange-red peel, glossy and dotted with numerous small oil glands; tender, thin, sweet and edible. The pulp, in 6 to 10 segments, very juicy, acidic, sweetly and up to 5 seeds.
It is cold, hardy and moderately drought tolerant plant. The trees are easily grown in a wide range of soils from clay-loam to limestone or sand. Calamondins are polyembryonic with 3 to 5 embryos each (Morton and Miami, 1987). It can be easily grown from seeds and also by vegetative method. Its flower is self-fertile and usually not required to cross pollination.
The calamondin plant is primarily grown as a house plant because of its bushy, normally dwarfed, nearly thorn less and year round bearing nature, and often called ‘miniature orange’. So, calamondins are widely grown as an ornamental tree. It has beautiful creamy and green variegated foliage and pretty orange coloured fruit in contrast to green leaves. Fragrant flowers appear in spring to summer and a heavy set of fruit follows, ripening in time. The ripe fruit holds well on the plant adding to its decorative show. The variegation makes it more desirable for container culture and fruit show off especially well against the beautiful bi-coloured leaves and thick foliage. However, only the ‘Peter’ calamondin variety shows the variegated nature.
Furthermore, the calamondin flesh has been used as a garnish for fish and chicken dishes in the Southeast Asia (Takeuchi et al., 2005). Its halves or quarters may be served with iced tea, seafood and meats, to be squeezed for the acid juice, which is primarily valued for making acid and sweet beverages, and is preserved into sweet pickles or marmalade. The fruits juice of calamondin can also be applied to the scalp after shampooing. It eliminates itching and promotes hair growth. Rubbing calamondin juice on insect bites banishes the itching and irritation. It is taken orally as a cough remedy and antiphlogistic. When slightly diluted and drunk warm it serves as a laxative.
