All Himalayan balsam plants germinate from the previous year’s seed. Himalayan Balsam grows very rapidly which necessitates readily available access to soil moisture which is why it has colonised river banks which have an abundance of moisture and nutrients. This causes a problem because Himalayan Balsam does not have an extensive root system and it is crowding out perennial plants that bind the river banks with their root systems. During flood events the river banks are then vulnerable to floodwater because of the lack of perennial plants. There are also claims that the height of the plant causes a problem by restricting the flow of the river.
Important Information on Himalayan Balsam
Himalayan Balsam has been added to Schedule 9 by The Wildlife and Countryside Act 1981 (Variation of Schedule 9) (England and Wales) Order 2010: this means that it is illegal to plant or otherwise cause to grow Himalayan Balsam in the wild.