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Japanese Knotweed
Bloom confirmed nearby
Reynoutria japonica
In the United States:
Invasive
· also called common knotweed, bamboo, fleeceflower, Knotweed —
Listed as invasive. Check local regulations — several jurisdictions restrict planting.
Japanese knotweed produces abundant nectar from its creamy-white flower panicles in late summer, providing a valuable late-season resource for honeybees when other forage is limited and sometimes yielding monofloral honey. The plant is a vigorous herbaceous perennial that spreads aggressively via rhizomes to form dense stands. Bees visit the flowers readily for both nectar and pollen.
| Nectar | high |
|---|---|
| Pollen | low |
| Bloom (US) | August–September |
| Duration | ~45 days |
| Type | Perennial |
| Sun | full |
Reported nearby
- Sep 30 — blooming now
- Sep 9 — blooming now
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