Homeowner’s shock after ‘wild garlic’ turns out to be invasive weed

Nation.Cymru staff

A south Wales homeowner spent more than a year believing a fast-growing plant in his garden was wild garlic before discovering it was an invasive species that can spread rapidly and potentially lead to fines if improperly disposed of.

Experts are now warning gardeners to be more cautious about identifying unfamiliar plants after the patch was confirmed to be three-cornered garlic, also known as three-cornered leek.

The plant, which produces white bell-shaped flowers and a strong garlic smell, is often mistaken for wild garlic, snowdrops or young daffodils.

However, it is classed as an invasive non-native species and is listed under Schedule 9 of the Wildlife and Countryside Act 1981, meaning it is illegal to allow it to spread into the wild.

Homeowners are responsible for ensuring it is properly controlled and disposed of, with breaches potentially resulting in fines of up to £5,000.

Jack Taylor, from South Wales, said he only realised what the plant was after seeking specialist advice.

“We genuinely thought we had a garden full of wild garlic,” he said.

“We had no idea it was an invasive plant. It was a shock finding out there are rules about it and you can actually get fined if it spreads.”

Specialists say the plant spreads through underground bulbs, making it difficult to eradicate completely once established.

Jennifer Holmes, from invasive species specialists Environment Controls, said the species was becoming an increasing problem because of confusion over its appearance.

“Three-cornered garlic is commonly mistaken for wild garlic due to its intoxicating garlic aroma when flowering – especially in sunlight,” she said.

“However, this is a highly invasive plant and is toxic to dogs if ingested.

“It’s also very difficult to completely eradicate and any efforts to do so by homeowners come with the threat of it returning if any fragments are left behind.”

She added that the species had escaped from horticulture during the 19th century and had since spread widely in some areas.

Herbicide

Experts advise people not to dispose of the plant in standard green waste bins because bulbs and fragments can survive and spread elsewhere.

Instead, professional removal involving herbicide treatment or excavation is often recommended.

Three-cornered garlic is still legally sold in some garden centres and online, despite concerns over its invasive nature.

The plant can be identified by its floppy triangular leaves and clusters of white flowers with a distinctive green stripe running down each petal.

Environment Controls offers a free identification service via their website.