Japanese knotweed (Persicaria japonica)

Japanese knotweed

Also known as: Bushy knotweed

Japanese knotweed is a robust, shade-tolerant perennial that often thrives along riverbanks and in moist woodland areas. It uniquely adapts to its lush habitat with broad, ovate leaves that can capture subdued sunlight. The plant features erect spikes of tiny, densely-clustered flowers, ranging from pink to white, that blossom in the late summer, providing a subtle yet attractive display.

Scientific classification

Species

Japanese knotweed (Persicaria japonica)

Pinks, cacti, and allies

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Perennial

Lifespan

Herb

Plant Type

1 m

Plant Height

Green

Leaf Color

Semi-evergreen

Leaf type

20 - 35 ℃

Ideal Temperature

Images of Japanese knotweed

Care Guide for Japanese knotweed

Every week

Water

Full sun

Sunlight

20 - 35 ℃

Ideal Temperature

Pruning: Japanese knotweed exhibits rapid, invasive growth, necessitating careful pruning from early to late spring to manage its spread. Cut back stems near the base and monitor regrowth. Regular maintenance promotes health and growth, while safety precautions and follow-up removals are essential for effective control.

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