Himalayan Balsam

Himalayan or Indian Balsam (Impatiens glandulifera) was introduced to Britain in 1839, but escaped from gardens and rapidly colonised riverbanks and areas of damp ground. Himalayan Balsam grows in dense stands that suppress the growth of native grasses and other flora. In the autumn, the plants die back, leaving the banks bare of vegetation and vulnerable to erosion.

Control

Himalayan Balsam often grows amongst bushes and brambles and inaccessible locations on riverbanks. The plant can be controlled by hand or machine cutting, but this is not always practical. Chemical control is by far the best option and involves spraying before flowering in the spring using approved pesticides followed by repeated sprays during the summer to prevent late germinating seedlings becoming established.

Identification

Native range

Western Himalayas

Stem

Pinky-red colour
Up to 3m tall - tallest annual plant in Britain
Hollow and jointed
Sappy and brittle

Leaves

Spear-shaped, with serrated edges
Shiny and dark green with a dark red midrib
Up to 15 cm long
Opposite or in whorls of three

Flowers 

Purplish-pink to pale pink
Slipper-shaped, on long stalks
June – October

Seeds 

White, brown or black
Produced from July – October
4-7mm diameter
4 – 16 seeds per pod