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Japanese Knotweed

Fallopia japonica

Please keep in mind that it is illegal to uproot a plant without the landowner's consent and care should be taken at all times not to damage wild plants. Wild plants should never be picked for pleasure and some plants are protected by law.
For more information please download the BSBI Code of Conduct PDF document.

Plant Data

Flowering Months:
JAN  FEB  MAR  APR  MAY  JUN  JUL  AUG  SEP  OCT  NOV  DEC
Order:
Caryophyllales
Family:
Polygonaceae (Dock)
Type:
Flower
Maximum Size:
2 metres tall
Habitats:
Farmland, meadows, riversides, roadsides, towns, wasteland, waterside, wetland, woodland.

Flower:
֍
White, 5 petals
 
Small and white, 5 petals. Forming branched spikes at the bases of the upper leaves.
Fruit:
3-angled seeds contained within a white winged papery encasing. Ripens around September.
Leaves:
The leaves can grow as large as 40cm long and 25cm wide. They grow alternate along the stems and are heart-shaped, toothless and have pointed tips. The young leaves are dark red. As the leaves being to mature, they turn green but the red veins persist a little longer. Eventually the entire leaf turns green, including the veins. The stems on which the leaves emerge from are zigzagged, changing directions at every leaf node. The mature stems are hollow.
Aroma:
Fragrant flowers which attract bees.
Other Names:
American Bamboo, Asian Knotweed, Asiatic Knotweed, Bombascus, Donkey Rhubarb, Elephant Ear's, False Bamboo, Fleeceflower, Gypsy Rhubarb, Hancock's Curse, Himalayan Fleece Vine, Itadori, Japanese Bamboo, Japanese Fleeceflower, Japanese Polygonum, Kontiki Bamboo, Mexican Bamboo, Monkey Fungus, Monkeyweed, Pea Shooters, Sally Rhubarb.
Frequency (UK):
Common  
Similar Species:
Distribution Map

Reproduced by kind permission of the BSBI.

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