With its tall stems and striking pink flowers, Himalayan Balsam (Impatiens glandulifera) might look like an attractive addition to your garden. In reality, it’s one of the UK’s most widespread invasive species, and one you should never plant.
Why It’s a Problem
Introduced to the UK in the 19th century as an ornamental, Himalayan Balsam quickly escaped gardens and spread along rivers, wetlands, and damp ground. It grows rapidly, reaching heights of up to 2.5m, and forms dense stands that outcompete native plants.
The real problem comes in autumn when its shallow roots die back, leaving riverbanks bare and vulnerable to erosion. Combined with explosive seed pods that can fire seeds up to 7 metres away, this makes it incredibly hard to control.
Like Japanese Knotweed, it’s listed under the Wildlife and Countryside Act 1981, which means it’s illegal to plant or allow it to spread in the wild.
How to Spot It
- Tall, hollow stems that snap easily
- Lance-shaped leaves with serrated edges
- Clusters of pink, helmet-shaped flowers (June–October)
- Seed pods that burst when touched
For detailed ID tips, see the RHS guide on Himalayan Balsam.
How to Deal With It
- Pull or cut before it sets seed: Young plants are shallow-rooted and easy to remove by hand.
- Never compost: Seeds can survive and spread. Dispose of safely as green waste where permitted.
- Work with neighbours or local groups: Community action is often needed to control infestations, especially along waterways.
Why It Belongs on the No Grow List
While its flowers may attract bees, the environmental cost of Himalayan Balsam far outweighs any benefits. It smothers native plants, destabilises soil, and creates a cycle of erosion and spread that damages ecosystems.
If you see it in the wild, consider joining a local balsam-bashing group to help keep it under control. And if you find it on your own plot, remove it before it becomes a bigger problem.
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