Family: Balsaminaceae

Origin: Himalayas

Himalayan balsam is also known as Indian balsam and policeman's helmet.

It is a beautiful suuculent annual species introduced to gardens in the 19th century, but has now become naturalised on lake and river banks across Northern Ireland.

These four photographs show the plant on the banks of the River Lagan in Co Down.

The plant now grows in such dense stands that it prevents the growth of native waterside plants.

The plant shows great variation in flower colour.

The flowers are followed by explosive seed capsules which hurl the seeds a considerable distance from the parent plant.