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Common Name: Round Kumquat

General Information

Fortunella japonica is an evergreen shrub that can grow up to 2.50 metres tall.
It has edible, medicinal and miscellaneous uses.

Known Hazards

None known

Botanical References

,

Range

E. Asia - China, Japan.

Habitat

Not known in a truly wild situation[].

Properties

Edibility Rating
Medicinal Rating
Habit	Evergreen Shrub
Height	2.50 m
Cultivation Status	Wild

Cultivation Details

Prefers a moderately heavy loam with a generous amount of compost and sand added and a very sunny position[]. Prefers a pH of 5 to 6[]. Plants are intolerant of water logging[].
This species is not hardy in the colder areas of the country, when dormant it tolerates temperatures down to about -5°c[]. The young growth in spring, even on mature plants, is frost-tender and so it is best to grow the plants in a position sheltered from the early morning sun[].
Kumquats are widely cultivated in China for their edible fruit, there are many named varieties[]. The plant is less vigorous, somewhat thorny and considerably more cold tolerant[] (the report gives no details of what this is in comparison to!). Kumquats are hardier than the various Citrus species since they cease growth when temperatures drop below 13°c but, for best results, it is best to grow them in a climate where temperatures do not fall lower than between 4 and 10°c[]. This is because the fruit is sweeter when it ripens in warm conditions[].

Edible Uses

Fruit - usually cooked and used in jellies, preserves etc[] or used as a flavouring, but it can also be eaten raw. The whole fruit, including the peel, is eaten[, ]. The fruit is acid whilst the peel is sweet[, ]. The peel is golden-yellow, smooth, thinner and somewhat sweeter than the oval kumquat, F. margarita[]. The fruit is rich in pectin and makes excellent marmalades and jellies[]. Vitamin C content is up to 0.24 mg/cc[]. The fruit is about 4cm long[].

Medicinal

The plant is antiphlogistic, antivinous, carminative, deodorant, stimulant[, ].
The leaves and fruit contain an essential oil, whilst the fruit also contains sugars and organic acids[]. The fresh fruit is antitussive and expectorant - in Vietnam it is steamed with sugar candy and used in the treatment of sore throats[]. It is said to be very good for infants[].

Other Uses

The fresh leaves and young twigs yield 0.21% essential oil that might be suitable for perfumery[].

Propagation

Seed - best sown as soon as it is ripe in a warm airy position in a greenhouse. When they are large enough to handle, prick out the seedlings into individual pots and grow them on in a greenhouse for at least their first two winters. Plant out in late spring or early summer after the last expected frosts and give some winter protection from the cold for a year or two.