Citrus japonica, the round-fruited kumquat
Citrus japonica
- Exposures
- Sun, Half-shade
- Hardiness (USDA)
- 8b (-9.4°C ≤ T° < -6.7°C)
- Lifecycle
- Perennial
- Foliage
- Evergreen
- Family
- Rutaceae
- Genus
- Citrus
- Species
- Citrus japonica
Other names:Fortunella japonica, Fortunella hindsii, Fortunella marumi
In 1846, Robert Fortune, an English traveler and botanist, brought back from one of his trips to China a shrub with a strange Cantonese name: gām-gwāt. Renamed kumquat in everyday language and Citrus japonica in Latin, the variety is classified, after much prevarication, in the Rutaceae family. Like other citrus fruits, it is prized for its fruit and ornamental properties.
How to recognize the kumquat, Citrus japonica?
In its natural environment, Citrus japonica is a tree that reaches a height of five meters and a spread of three meters. In our latitudes, the kumquat doesn't exceed 2.5 meters in height and 1.75 meters in width. In pots, growth is even more limited. The plant can even be grown as a bonsai!
This evergreen shrub can be recognized by its dense crown and thorny branches. The fragrant, slightly lanceolate leaves are strongly veined. Blades measure between four and eight centimetres. Twigs are a brilliant dark green all year round.
Flowering takes place from March to June. Bunches of white flowers appear between the leaves, spreading a fragrance similar to that of Citrus sinensis.
These are replaced by golden-yellow fruits, two to four centimetres long. Citrus japonica kumquats are round, while those of Citrus margarita are oval. Their flesh is sweet and their core bitter. They are eaten as is, in jam or marinated in syrup.
In Asia, Citrus japonica and its round fruit symbolize good luck. Whereas we used to give oranges at Christmas, the Chinese prefer to exchange kumquats for the Lunar New Year.
Our care tips
Maintaining a Citrus japonica is not difficult. Above all, you need to protect it from frost in winter and provide it with the nutrients it needs to grow. With the right potting soil and regular fertilizing, you'll soon be enjoying your own citrus fruits.
The Citrus japonica citrus trees need regular watering all year round. During hot spells, water early in the morning or in the evening. Water evaporates less quickly, and your shrub benefits from it for longer.
Watering
To find out if your plant is thirsty, stick your finger in the soil. When the surface is dry (about three centimetres), then you need to water your Citrus japonica. The Citrus japonica like moisture, but not stagnant water. Make sure that the potting soil remains moist, but that the rootlets are not drowned.
If you can, use non-calcareous water such as rainwater or filtered water.
Also make sure that water doesn't stagnate in the saucer or planter.
If you can, use non-calcareous water such as rainwater or filtered water.
Also make sure that water doesn't stagnate in the saucer or planter.
Repotting
In spring, transfer your Citrus japonica to a larger pot, so that it can continue to grow.
When roots are sticking out of the pot or visible on the surface, it's time to repot!
To prepare your Citrus japonica for repotting, soak the root ball. Then gently loosen the root ball.
Choose a terracotta pot or a wooden planter. Both materials promote water evaporation and reduce the risks associated with excessive watering. Make sure the container has drainage holes to allow water to drain.
Place a layer of clay pellets or gravel at the bottom to aid drainage.
Fill the rest with a rich substrate, such as a special citrus potting mix or general-purpose potting mix. You can make your own mix using:
- one-third potting mix;
- one-third garden soil;
- pozzolan.
Place your shrub in the center. The top of the root ball should be two centimeters below the rim of the pot. Fill in with substrate and firm it down to remove air pockets. When planting, be sure not to bury the root collar.
Fertilization
You can stimulate the development of your plant during its growth phase, in spring and summer, with fertilizer.
The Citrus japonica are greedy plants. They need to be fertilized. Feed yours with a special liquid or granulated citrus fertilizer.
Cleaning
Over time, dust accumulates on the leaves, slowing down photosynthesis. To remove it, clean the foliage with a clean, damp sponge.
Harvest
Pick the fruit from the tree when it's ripe.
Prune
Size is not essential. It only helps to control shape and development and improves fruiting. When pruning, always use clean, sharp pruning shears.
Citrus trees flower and fruit on the year's wood. To maintain the compact, rounded shape of your shrub, remove dead branches and shoots growing along the trunk. You can also aerate the center by removing some shoots that have already borne fruit in previous years.
If you want to improve your harvest, you can also carry out a fruiting pruning operation: one month after the appearance of a new shoot, prune it back to a height of 20 centimetres.
Pinch
Pinch your Citrus japonica during its growing season.
Pinch stem ends to encourage branching and maintain dense growth.
Planting
Once the last spring frosts have passed, you can plant.
Find them a place sheltered from the wind and isolated from other plants. Citrus plants have shallow roots and don't like to share their space.
Dig a hole 70 centimetres wide and 1 metre in diameter. While you're at it, soak the root ball.
Plant the plant in the middle, with the top of the rootball level with the ground. Take care not to bury the collar.
The Citrus japonica plants thrive in light, well-drained, rich soil. When filling in, add potting soil or citrus soil to your garden soil. Tamp and water.
Diseases / Threats
Information
- Lifecycle
- Perennial
- Foliage
- Evergreen
- Exposures
- SunHalf-shade
- Substrate
- Humus soil
- Planting methods
- Open groundIn potsIn tubs
- Categories
- ShrubFruit tree
- Tag
- Edible fruit
- Origin
- East Asia
- Hardiness (USDA)
- 8b (-9.4°C ≤ T° < -6.7°C)
- Leaf color
- Dark green
- Flower color
- White
- Fruit color
- Yellow
Discover plants from the same family
Lemon tree
Citrus x limon
Clementine tree
Citrus x clementina
Mandarin orange tree
Citrus reticulata
Orange tree
Citrus sinensis
Find out more
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