TV gardener Alan Titchmarsh has urged people to keep an eye out for Colorado beetles, which pose a “savage” threat to the British potato industry.
The insects and their larvae feed on the foliage of potatoes and other plants, including aubergines and peppers, which can weaken the crops and reduce yield.
The invasive species was confirmed in a field in Kent after a laboratory diagnosis in 2023, marking the first known case on UK soil in 50 years.
If the beetle is not eradicated and spreads across the country, it could have a significant economic impact on the British potato industry.
The case, in which dozens of the insects at different stages were found on three potato plants in a field in Kent, prompted intense eradication and monitoring efforts, including flying drones over fields to spot the damage done by the beetles.
Officials are hopeful that the outbreak – the first case of a breeding population since the 1970s – can be declared eradicated by the end of this year, but warned the public need to remain vigilant to the threat.
Speaking to the PA news agency at the Chelsea Flower Show, Mr Titchmarsh said: “It devastates potato crops and we need all the crops we can get in this country.
“It’s so savage it’ll wipe crops out. It’s like locusts – it’s that fast.”
He said the secret is to “stamp it out before it becomes reality”, adding: “There’s so much waiting on the doorstep.”
“Don’t panic about it, just be vigilant and then we can keep it out,” he said.
The presenter also highlighted the species’ threat to UK food security, as the country only grows 50% of the vegetables and 12% of the fruit it needs, importing the rest.
“It’s really, really important for our exports and for feeding ourselves,” he said.
“We need to grow more food not less and with outbreaks like this, our potato exports are in grave danger.”
Those who spot the insect are urged to catch it in a container if possible and contact the Animal and Plant Health Agency (APHA) with a photo and location details.
We’ll be at #RHSChelsea Flower Show next week, sharing information on the #ColoradoBeetle: a pest of our precious #potato plants.
— APHA (@APHAgovuk) May 18, 2025
If you #GrowYourOwn or you just love your chips, crisps & jacket potatoes, come and find out how to help protect our spuds!@The_RHS @BBCiPlayer #BTS pic.twitter.com/OWuAjCbpHd
The 6mm to 11mm beetle, which does not represent a risk to human health, is yellow or cream with 10 black stripes, and an orange head with irregular black spots.
Its larvae are a pinkish red or orange colour, with black spots along each side, a black head, and are up to 15mm in length.
The beetles have been known to be imported into the UK as hitchhikers on plants, such as leafy vegetables, salad leaves, fresh herbs, grain and frozen vegetables.
Professor Nicola Spence, the Environment Department’s chief plant health officer, said: “Colorado beetle poses a significant threat to plants and the wider potato industry.
“The public have an important role to play in helping us take swift and effective action to protect UK biosecurity.”
She warned that the beetle was a “really big threat, the economic impact it could have is huge”.
“Because it can hitchhike that’s why we need the public to be vigilant. It will pop up in unexpected places,” she warned.
Dr Jenny Stewart, APHA interim chief executive, said: “Public vigilance was key to eradicating the beetle in the 1970s, and we really need home gardeners, allotmenteers and farmers to step up again, and identify and report suspected sightings to protect potato crops.
“Our surveillance capabilities protect UK borders from a wide range of plant pests and diseases, including the Colorado beetle, but we cannot do this without the help of the public.”
APHA is exhibiting at this year’s Chelsea Flower Show to raise awareness of the impact this pest can have on UK food security and the potato industry, after outbreaks in the 1930s, 1950s and the 1970s.
