Family: OXALIDACEAE
Genus: Averrhoa
Species: carambola
Species Author: L.
Vernacular: Carambola, Star Fruit, Ansu - Pohnpeian [Balick 3938]
The Carambola tree is slow-growing, short-trunked with a much-branched, bushy, broad, rounded crown and reaches 20 to 30 ft (6-9 m) in height. Its deciduous leaves, spirally arranged, are alternate, imparipinnate, 6 to 10 in(15-20 cm) long, with 5 to 11 nearly opposite leaflets, ovate or ovate-oblong, 1 1/2 to 3 1/2 in (3.8-9 cm) long. The leaves are soft, medium-green, and smooth on the upper surface, finely hairy and whitish on the underside. The leaflets are sensitive to light and more or less inclined to fold together at night or when the tree is shaken or abruptly shocked. Small clusters of red-stalked, lilac, purple-streaked, downy flowers, about 1/4 in (6 mm) wide, are borne on the twigs in the axils of the leaves. The showy, oblong, longitudinally 5- to 6-angled fruits, 2 1/2 to 6 in (6.35-15 cm) long and up to 3 1/2 (9 cm) wide, have thin, waxy, orange-yellow skin and juicy, crisp, yellow flesh when fully ripe. Slices cut in cross-section have the form of a star. The fruit has a more or less pronounced oxalic acid odor and the flavor ranges from very sour to mildly sweetish. The so-called "sweet" types rarely contain more than 4% sugar. There may be up to 12 flat, thin, brown seeds 1/4 to 1/2 in (6-12.5 mm) long or none at all.
(Morton, J. 1987. Fruits of warm climates.)
In India, the ripe fruit is administered to halt hemorrhages and to relieve bleeding hemorrhoids. The dried fruit or the juice may be taken to counteract fevers. A conserve of the fruit is said to allay biliousness and diarrhea and to relieve a "hangover" from excessive indulgence in alcohol. A salve made of the fruit is employed to relieve eye afflictions.
In Brazil, the carambola is recommended as a diuretic in kidney and bladder complaints, and is believed to have a beneficial effect in the treatment of eczema.
In Chinese Materia Medica it is stated: "Its action is to quench thirst, to increase the salivary secretion, and hence to allay fever."
A decoction of combined fruit and leaves is drunk to overcome vomiting. Leaves are bound on the temples to soothe headache. Crushed leaves and shoots are poulticed on the eruptions of chicken-pox, also on ringworm.
The flowers are given as a vermifuge. In southeast Asia, the flowers are rubbed on the dermatitis caused by lacquer derived from Rhus verniciflua Stokes.
Burkill says that a preparation of the inner bark, with sandalwood and Alyxia sp., is applied on prickly heat. The roots, with sugar, are considered an antidote for poison. Hydrocyanic acid has been detected in the leaves, stems and roots.
A decoction of the crushed seeds acts as a galactagogue and ernmenagogue and is mildly intoxicating. The powdered seeds serve as a sedative in cases of asthma and colic.
(Morton, J. 1987. Fruits of warm climates.)
The acid types of Carambola have been used to clean and polish metal, especially brass, as they dissolve tarnish and rust. The juice will also bleach rust stains from white cloth. Unripe fruits are used in place of a conventional mordant in dyeing.
Carambola wood is white, becoming reddish with age, close-grained and medium-hard. It has been utilized for construction and furniture.
(Morton, J. 1987. Fruits of warm climates.)
(Information for this species compiled and recorded by Camelia Cirnaru, NTBG Consultant.)
The Carambola is believed to have originated in Ceylon and the Moluccas but it has been cultivated in southeast Asia and Malaysia for many centuries. It is commonly grown in the provinces of Fukien, Kuangtung and Kuangsi in southern China, in Taiwan and India. It is rather popular in the Philippines and Queensland, Australia, and moderately so in some of the South Pacific islands, particularly Tahiti, New Caledonia, Netherlands, New Guinea, Guam and Hawaii.
(Morton, J. 1987. Fruits of warm climates.)
Ripe Carambolas are eaten out-of-hand, sliced and served in salads, or used as garnish on avocado or seafood. They are also cooked in puddings, tarts, stews and curries. In Malaya, they are often stewed with sugar and cloves, alone or combined with apples. The Chinese cook Carambolas with fish. Thais boil the sliced green fruit with shrimp. Slightly underripe fruits are salted, pickled or made into jam or other preserves. In mainland China and in Taiwan, Carambolas are sliced lengthwise and canned in sirup for export. In Queensland, the sweeter type is cooked green as a vegetable. Cross-sections may be covered with honey, allowed to stand overnight, and then cooked briefly and, put into sterilized jars. Some cooks add raisins to give the product more character. A relish may be made of chopped unripe fruits combined with horseradish, celery, vinegar, seasonings and spices. The ripe fruits are sometimes dried in Jamaica.
Carambola juice is served as a cooling beverage. In Hawaii, the juice of sour fruits is mixed with gelatin, sugar, lemon juice and boiling water to make sherbet. Filipinos often use the juice as a seasoning.
To make jelly, it is necessary to use unripe "sweet" types or ripe sour types and to add commercial pectin or some other fruit rich in pectin such as green papaya, together with lemon or lime juice.
The flowers are acid and are added to salads in Java. Also, they are made into preserves in India. The leaves have been eaten as a substitute for sorrel.
(Morton, J. 1987. Fruits of warm climates.)
Starfruit was introduced into southern Florida before 1887 and was viewed mainly as a curiosity until recent years when some small groves have been established and the fruits have been used as "conversation pieces" to decorate gift shipments of citrus fruits.
(Morton, J. 1987. Fruits of warm climates.)
We currently have 11 herbarium specimens for Averrhoa carambola in our collection. Click on any specimen below to view the herbarium sheet data.
- 017240 - collected by Shawn Lum in 1983
- 017241 - collected by Richard A. Howard in 1985
- 002171 - collected by Tim Flynn in 1989
- 015858 - collected by Tim Flynn in 1994
- 033315 - collected by Michael J. Balick in 1998
- 040542 - collected by David H. Lorence in 2002
- 039959 - collected by Steve Perlman in 2003
- Unassigned - collected by Liloa Dunn in 2003
- 040999 - collected by Liloa Dunn in 2003
- 072612 - collected by David H. Lorence in 2010
- 092157 - collected by David H. Lorence in 2022