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- Japanese Bitter Orange (Poncirus trifoliata)
Japanese Bitter Orange (Poncirus trifoliata)
The Japanese Bitter Orange is a relatively frost-hardy citrus plant with golden-yellow fruits, attractive blossoms and striking thorns.
Leaves
Elliptic ovate to obovate, ternate. Alternate dark green, slightly leathery, translucent spotted deciduous leaves. 3 - 6 cm long with blunt tip. Leaves at the sides are smaller with skew base. Decorative yellow colour in autumn.
Flowers
Flowering period IV-V. Sweetly fragrant, white, broadly spaced blossoms, 3 - 5 cm wide, monoecious. Alternate petal arrangement. Blossoms appear before the leaves sprout and are decorative.
Fruits
Round, golden-yellow, tomentose berries. Numerous almost white seeds 0.6 - 1.2 cm long. Very sour tasting fruit, inedible. Decorative, persistent fruits, tendency to drop fruit.
Photos
Types of damage
Application
Flowering hedges, forage for honey-bees, public areas, parks, urban areas, pedestrian precincts, container plants, wintergardens, private gardens, kitchen gardens, front gardens, verandas, atrium gardens
Native regions
Northeast Asia
Location parameters
Light: sunny to off-sun; soil depth: medium to very deep; soil mixture: loose, 1/3 loamy garden soil, 2/3 humus; soil structure: normal to airy; soil quality: low to normal; soil: slightly dry to fresh; moisture: to be avoided; pH value: slightly acid to moderately alkaline; nutrient concentration: normal to high; temperature: growth period: daytime: 18 °C to over 25 °C, night: 11 °C to 25 °C, resting period: -24 °C to 11 °C. Often used as root-stock for the entire Citrus genus.
Demands
Tolerates heat, stagnant moisture and urban climates, also tolerates flooding, wind-resistant, limited salt-tolerance. Soil compaction must be avoided.
Growth
Height of growth: 1 m to 7 m. Spread: 2 m to 9 m. Slow-growing shrub or tree with wide, bushy branches, shaggy spreading rounded crown, often multi-stem and crooked.
Leaves
Elliptic ovate to obovate, ternate. Alternate dark green, slightly leathery, translucent spotted deciduous leaves. 3 - 6 cm long with blunt tip. Leaves at the sides are smaller with skew base. Decorative yellow colour in autumn.
Flowers
Flowering period IV-V. Sweetly fragrant, white, broadly spaced blossoms, 3 - 5 cm wide, monoecious. Alternate petal arrangement. Blossoms appear before the leaves sprout and are decorative.
Fruits
Round, golden-yellow, tomentose berries. Numerous almost white seeds 0.6 - 1.2 cm long. Very sour tasting fruit, inedible. Decorative, persistent fruits, tendency to drop fruit.
Bark
Green longitudinally furrowed outer bark, with decorative thorns.
Roots
Shallow-rooting, branched.