Round Kumquat
Fortunella japonica

Family: Rutaceae

What it is like

Fortunella japonica is an evergreen Shrub growing to 2.5 m (8ft 2in). See above for USDA hardiness. It is hardy to UK zone 9 and is frost tender. It is in leaf all year. The species is hermaphrodite (has both male and female organs). Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. 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.

Height (m): 2.5

Where it is found

Not known in a truly wild situation.

E. Asia - China, Japan.

Conservation Status:

Countries/locations it is found in

How it is used

Food

Rating: 3

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.

Pectin: a substance that is used to thicken jams etc and as a culture medium in laboratories.

Medicine

Rating: 1

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.

Antiphlogistic: Reduces inflammation.

Antitussive: Prevents or relieves coughing.

Antivinous: Treats addiction to alcohol

Carminative: Reduces flatulence and expels gas from the intestines.

Deodorant: Masks smells. Is this medicinal?

Expectorant: Clears phlegm from the chest by inducing coughing.

Stimulant: Excites or quickens activity of the physiological processes. Faster acting than a tonic but differing from a narcotic in that it does not give a false sense of well-being.

Vitamin C: Plants good for their vitamin C content

Other

Rating: 2

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

Deodorant: A pleasant smelling plant that is used on the body to mask the human smell.

Essential: Essential oils that are used in perfumery, medicines, paint solvents, insect repellents etc.

Pectin: A substance that is used to thicken jams etc and as a culture medium in laboratories.

Scented Plants: Plants noted for their scent

How it is grown

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.

Propagating it: 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.

Best place to grow: Woodland Garden Sunny Edge; South Wall. By. West Wall. By.

Habit: Shrub

Hardiness: 8-11

Growth:

Soil: Light (sandy), medium, heavy (clay)

Shade: Semi-shade, no shade

Moisture: Moist

Things to keep in mind

Its other names

Local names

Synonyms

Citrus japonica.