How to control acanthus

Previous garden owners created an openbottomed 'container' for the acanthus, by cementing together large flinty stones. This sits slightly above and mostly below ground

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Q We recently moved to a house with a garden that is overrun with a plant called acanthus. It is a good-looking thing, but how can I control it? Penny Theakston, Tunstall, Staffs.

A In many ways, bear’s breeches (usually represented in gardens by Acanthus mollis) are handsome plants. When properly marshalled into a space from where they cannot escape, they add architecture to our gardens.

Originally from Mediterranean regions and north-west Africa, these plants make crowns of leaves that have inspired design for thousands of years, decorating the Corinthian columns of ancient Greece, Mediaeval manuscripts and William Morris wallpaper alike.

In the right place, their long display of 5ft (1.5m)-tall flower spikes, toughness and resilience to deer and rabbits is a plus – but in some parts of the world, they have escaped into the landscape and are an invasive nuisance. Acanthus, you see, is a potential thug.