Nature Table: Indian Balsam

Also known as Himalayan Balsam, this attractive plant is a garden escapee which is on the official invasive aliens list. It grows mainly on river banks but occasionally on waste ground away from water.

It is large, reaching up to 2m in height, and tends to grow in dense clumps that spread rapidly and can suppress native bank-side vegetation. The large and curiously-shaped flowers, in various shades of pink, are in bloom from July through to October. In Britain another name for the plant is ‘policeman’s helmet’ because the flower is shaped rather like the traditional head gear of the London Bobby.

The flowers ripen into seed pods which explode when they are ripe. Each plant is capable of shooting up to 800 seeds for a distance of 7m and if the seeds land in water they float downstream. The efficiency of this seed distribution method is what makes it so prolific and potentially invasive. Indian balsam is a close relative of the Busy Lizzie, although it looks different.