Longan, Lungan, Dragon's Eye, Cat's Eye

Dimocarpus longan

Physical Characteristics

Dimocarpus longan is an evergreen Tree growing to 12 m (39ft) by 12 m (39ft) at a fast rate. See above for USDA hardiness. It is hardy to UK zone 9. The plant is self-fertile. It is noted for attracting wildlife. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils and prefers well-drained soil. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

Distribution

E. Asia - China, India, Sri Lanka, Myanmar, Thailand, Cambodia, Laos, Vietnam, Malaysia, Indonesia, Philippines.

Habitats

Edible Uses

Edible Parts: Fruit Edible Uses: Fruit - raw or cooked. The mucilaginous flesh is whitish, translucent and somewhat sweet, though not as flavoursome as the related lychee(Litchi chinensis)[ 301 , 303 ]. It is delicious eaten raw and can also be dried, preserved in syrup, cooked in sweet and sour dishes or in soups[ 301 ]. The globose fruits are 12 - 25mm in diameter, with a thin, brittle, yellow-brown to light reddish-brown rind[ 303 ]. Longans are much eaten fresh, out-of-hand, but some have maintained that the fruit is improved by cooking[ 303 ]. In China, the majority are canned in syrup or dried. For drying, the fruits are first heated to shrink the flesh and facilitate peeling of the rind. Then the seeds are removed and the flesh dried over a slow fire[ 303 ]. The dried product is black, leathery and smoky in flavour and is mainly used to prepare an infusion drunk for refreshment[ 303 ].

Medicinal Uses

Antihydrotic Febrifuge Hypnotic Stomachic Styptic Tonic Vermifuge The flesh of the fruit is administered as a stomachic, febrifuge and vermifuge, and is regarded as an antidote for poison. A decoction of the dried flesh is taken as a tonic and treatment for insomnia and neurasthenic neurosis[ 303 ]. In both North and South Vietnam, the 'eye' of the longan seed is pressed against a snakebite in the belief that it will absorb the venom[ 303 ]. Leaves and flowers are sold in Chinese herb markets but are not a part of ancient traditional medicine. The leaves contain quercetin and quercitrin[ 303 ]. The seeds are administered to counteract heavy sweating and the pulverized kernel, which contains saponin, tannin and fat, serves as a styptic[ 303 ].

Known Hazards

None known