Himalayan Balsam Himalayan balsam (Impatiens glandulifera) is a relative of the busy Lizzie and is known by a wide variety of common names, including Indian balsam, jumping jack and policeman's helmet.

Introduced to the UK in 1800, it is now naturalised, especially on riverbanks and increasingly in waste places and has become a problematical weed. Himalayan balsam tolerates low light levels and, in turn, tends to shade out other vegetation, impoverishing habitats.It is a tall, robust, annual producing clusters of purplish pink helmet-shaped flowers. These are followed by seed pods that open explosively when ripe, shooting their seeds up to 7m (22ft) away. Each plant can produce up to 800 seeds.

It typically grows to 1 to 2 meters high, with a soft green or red-tinged stem, and lanceolate leaves 5-23 cm long. The crushed foliage has a strong musty smell. The flowers are pink, with a hooded shape

For more information download the invasive weed leaflet here