Elaeagnus formosana

Nakai

Elaeagnaceae Edible: Fruit 288 iNaturalist observations

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Summary

Evergreen shrub with year-round foliage and flowering from September to December; seeds ripen April to June. Hermaphroditic and insect-pollinated. Fixes nitrogen. Grows in light sandy, medium loamy, and heavy clay soils, preferring good drainage. Tolerates mildly acidic, neutral, and basic soils including very alkaline conditions. Semi-shade or full sun. Drought-tolerant and maritime-hardy.

Description

An evergreen shrub. It can be climbing. The young branches are silvery brown. The leaves are narrowly oval and 4-11 cm long by 2-5 cm wide. The flowers can occur singly or in groups of 2-6. The flowers are white. The fruit are oval and 1-2 cm long. The seed have 8 ribs.

Edible Uses

The fruit can be eaten raw or cooked, but must be fully ripe before it can be enjoyed raw — if even slightly under-ripe it will be quite astringent. The ovoid fruit grows up to 16mm long and contains a single large seed.

Medicinal Uses

The fruit is a very rich source of vitamins and minerals, particularly vitamins A, C and E, flavanoids and other bio-active compounds. It also provides a fairly good supply of essential fatty acids, which is unusual for a fruit. It is being investigated for its potential to reduce the incidence of cancer and to halt or reverse cancer growth.

Distribution

It occurs throughout Taiwan below 2,000 m above sea level.

Where It Grows

Asia, Taiwan,

Cultivation

We have very little information on this species and do not know if it will be hardy in Britain, though judging by its native range it could succeed outdoors at least in the milder parts of this country. The following notes are based on the general needs of the genus. Succeeds in most soils that are well-drained. Prefers a light sandy soil that is only moderately fertile, succeeding in poor and dry soils. Very drought and wind resistant. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby. An excellent companion plant, when grown in orchards it can increase yields from the fruit trees by up to 10%. This species is notably resistant to honey fungus.

Propagation

Seed is best sown as soon as it is ripe in a cold frame. It should germinate in late winter or early spring, though it may take 18 months. Stored seed can be very slow to germinate, often taking more than 18 months; a warm stratification for 4 weeks followed by 12 weeks of cold stratification can help. Prick out seedlings into individual pots as soon as they are large enough to handle and plant out when at least 15cm tall. Cuttings of half-ripe wood, 7–10cm with a heel, taken in July/August in a frame. Cuttings of mature wood from the current year's growth, 10–12cm with a heel, taken in October/November in a frame — the cuttings are rather slow and difficult to root, so leave them for 12 months. Layering in September/October takes 12 months.