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Himalayan Balsam: The Facts

Posted: Monday 10th July 2017 by RiverSearch

This pretty pink plant was first introduced to Britain as an ornamental in 1839, but soon found its way out of gardens and into the countryside, where it has been spreading rapidly ever since

The largest annual plant in Britain, growing up to 2.5m high from seed in a single season. Himalayan balsam spreads quickly as it can project its seeds up to four metres. Where it grows it can shade out our native species reducing biodiversity and putting rarer species at risk of local extinction.

It is an annual plant so dies back during the winter leaving banks at risk of erosion. 


Commonly found along riverbanks and streams, around ponds and lakes, and in ditches and damp meadows.

What's the problem?

It spreads quickly and forms dense thickets, altering the ecological balance and character of wetland habitats. Many seeds drop into the water and contaminate land and riverbanks downstream, but the explosive nature of its seed release (seeds can be projected up to four meters away) means it can spread upstream too. It produces a lot of pollen over a prolonged season and is attractive to pollinating insects. There is concern that its presence may therefore result in decreased pollination for other native plants.

This species is listed on Schedule 9 of the Wildlife and Countryside Act in England and Wales therefore, it is also an offence to plant or otherwise cause to grow these species in the wild.

Removing Himalayan balsam

The best times for removal of this species are the months of June and July. The plant goes to seed during August by which time it is pointless to remove. Himalayan Balsam is possibly the easiest of all the invasive species to remove as it can be pulled up easily just using your hands. Its shallow roots mean it comes away from the soil easily. When pulling it is important that the whole plant is removed as it can grow back from the base of the stem.Once pulled it can be piled up away from the river into a heap where it will compost down relatively quickly.

The sheer extent of himalayan balsam means it is up to all of us if we are to get on top of the problem in Surrey. We encourage local groups to organise their own balsam bashing tasks in their areas.

Alernatively you can come and join one of the tasks being run as part of Invasive Species Month by visiting:


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