Averrhoa carambola Arkin - Star fruit tree

The 'Arkin' Starfruit Tree (Averrhoa carambola) is an exotic fruit tree prized for its dense foliage, rapid fruiting, flowering, and golden star-shaped fruits with a sweeter taste, known as starfruit. Native to tropical Asia, it can be grown in pots, greenhouses, or conservatories in our climate. It may bear fruit if heat, humidity, and light are well controlled. Its juicy, mildly tangy starfruit is as beautiful as it is delicious, enjoyed fresh, as juice, or in cooking.

The 'Arkin' Starfruit Tree (Averrhoa carambola) belongs to the Oxalidaceae family. The species is a fruit tree native to Southeast Asia, particularly Malaysia, Indonesia, and southern China. Today, it is widely cultivated in tropical and subtropical regions worldwide, including India, Southeast Asia, South America, Florida, and Hawaii.

'Arkin' is a variety prized for the sweetness of its fruits and their low acidity. This variety was developed by Morris Arkin, an amateur horticulturist from Coral Gables, Florida, in the 1970s. His work made starfruit more accessible and popular, particularly in Florida, where the 'Arkin' variety now accounts for 98% of cultivated areas.

This slow-growing tree typically reaches a height of 6 to 9 metres in the ground, with a short trunk and a broad, rounded crown. When grown in a large pot and regularly pruned, its size remains more modest: around 2.50 m tall and 1.50 m wide. Its spirally arranged compound leaves measure between 15 and 20 cm in length and consist of 5 to 11 opposite, ovate to ovate-oblong, 3.8 to 9 cm long leaflets. The upper surface of the leaves is smooth and medium green, while the underside is finely hairy and whitish. The leaves exhibit a unique sensitivity: they fold at night or in response to sudden stimuli, a phenomenon known as nyctinasty.

The starfruit tree's small, bell-shaped flowers measure about 6 mm in diameter and have five petals coloured lilac or streaked with purple, with whitish edges. They appear in loose clusters at the ends of branches or sometimes on larger stems and the trunk. Flowering can occur several times a year, especially in tropical climates, adding a decorative touch to the tree. In our climate, it occurs during the warmer months, from spring to summer.

The star-shaped fruit, known as starfruit, is oblong and typically has five longitudinal ridges: when sliced, its cross-section forms a star. The fruits measure between 6.35 and 15 cm in length and up to 9 cm in width. The skin is thin, waxy, and yellow-orange when ripe, while the flesh is juicy, crisp, and yellow. The taste ranges from very tart to mildly sweet, depending on the variety. The 'Arkin' Starfruit Tree is known for its ability to produce low-acid fruits once it reaches a height of 90 cm to 1.20 m, when grown in full sun and at temperatures between 21 and 27 °C. Each fruit may contain up to twelve flat, thin, brown seeds, measuring 6 to 12.5 mm in length, though some cultivated forms produce seedless fruits.

The starfruit tree is often self-fertile, but cross-pollination can improve fruit quality and yield. Insects, such as bees, play a crucial role in this process. Encouraging their presence is beneficial for optimising fruiting. Otherwise, manual pollination using a brush to transfer pollen from flower to flower will be necessary.

Harvest starfruit when the fruits have turned golden yellow, indicating ripeness. Pick them gently by hand to avoid damaging the fruits and the tree. Starfruit is often used to garnish dishes due to its star shape when sliced. It can be eaten fresh, juiced, or used in cooking to prepare coulis and desserts.

The starfruit tree is a multi-faceted tree, valued for both its ornamental appeal and the flavour of its fruits. Its cultivation requires specific conditions, but it rewards the attentive gardener with decorative and delicious starfruit. Discover our range of unique and exotic fruit trees.