Peter Dowdall: Beware the beautiful bullies when choosing garden plants

Because some plants are virtually impossible to eradicate once established in your border or lawn, and will colonise every corner

Hedgerow of wild montbretia in West Cork. The plant we see growing in Ireland was originally an ornamental hybrid created in 1879, a cross between two South African species. File picture

We all know the story: you spot something in the garden centre in spring, something lush and vigorous and reasonably priced, it steals your heart with its pretty flowers or foliage, you bring it home, you plant it, and for a while everything is fine.

Then, bit by bit, even while you were sleeping, it just begins to make itself a bit too welcome, inching forth nearly unseen until then, it starts to take over. By the time you understand what you've done, you're on your knees with a trowel and a growing sense of defeat, wondering how you fell for it in the first place.