Himalayan Balsam: A pretty flower but a major problem

Himalayan balsam (Impatiens glandulifera) is a relative of the busy Lizzie, but reaches well over head height, and is a major weed problem.
It is mainly found on riverbanks and waste land, but can also invade gardens. It grows rapidly and spreads quickly, smothering other vegetation as it goes.
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How can I identify Himalayan Balsam?

Himalayan Balsam typically grows to 1-2 m high, with a soft green or red-tinged stem, and long narrow, serrated-edge leaves leaves 5-20 cm long. The crushed foliage has a strong musty smell.

The flowers are pink, with a hooded shape, 3-4 cm tall and 2 cm broad; the flower shape has been compared to a policeman's helmet, giving rise to the alternative common name Policeman's Helmet. After flowering between June and October, the plant forms seed pods 2-3 cm long and 8 mm broad, which explode when disturbed, scattering the seeds up to 7 metres .

The aggressive seed dispersal, coupled with high nectar production which attracts pollinators, often allows the Himalayan Balsam to outcompete native plants. In the UK the plant was first introduced in 1839 at the same time as Giant Knotweed.

How can I get rid of it?

Knotweed NI can often eradicate Himalayan Balsam in a single visit, as well as offering suggestions for planting the unsightly area left by its removal.