Lookalike guide
Himalayan balsam vs Rosebay willowherb
Both make tall pink stands along rivers in summer, so people often pull the wrong one.
Rosebay willowherb (Chamaenerion angustifolium): Native wildflower — good for wildlife.
| Feature | Himalayan balsam | Rosebay willowherb |
|---|---|---|
| Flowers | Pink hooded 'policeman's helmet' flowers | Flat four-petalled flowers in a tall spike |
| Leaves | Toothed, in pairs or threes round the stem | Narrow, untoothed, spiralling singly |
| Stems | Fleshy, translucent, red-tinged, snap easily | Firm and thin |
| Seed | Pods that explode when touched | Fluffy white seed drifting on the wind |
Quick test
Squeeze a ripe pod — if it pops, it is balsam.