WARRINGTON is the worst affected place in Cheshire for Japanese knotweed.

Japanese knotweed has the potential to grow up through cracks in concrete, tarmac driveways, pathways, drains and cavity walls, causing thousands of pounds worth of damage.

Invasive plant specialist Environet has revealed Cheshire’s Japanese knotweed hotspots in Cheshire in 2024.

The analysis is based on the latest data from its interactive online tracker, Exposed: The Japanese Knotweed Heatmap, which is updated with new verified sightings reported by Environet’s team and members of the public throughout the year.

This year in Cheshire, Warrington had the most reports of Japanese knotweed with 284 incidences.

Widnes followed with 121 incidences, with Northwich in third with 116.

There are a total of 1,319 verified knotweed sightings in Cheshire, or 0.56 incidences in every 1km². In the national Japanese knotweed hotspots list, Cheshire is the 13th worst affected county in England.

Over the next few weeks knotweed will start to die back, as temperatures cool and light levels drop, sending the plant into its dormant winter phase. Its green leaves will die and fall from the branches, the stems will turn brown and brittle, and after the first few frosts the plant will have completely died back, leaving only the dead canes remaining. However, the plant will re-emerge next spring, so autumn and winter is the ideal time to excavate it when the garden is not in use.

Emily Grant, director of Environet, said, “With over 60,000 known infestations of Japanese knotweed on our heatmap, we have a clear picture of its prevalence across the England and Wales. Knotweed is easily identifiable during summer, but it’s a perennial plant so as we head through the autumn and into winter, the above-ground growth dies back and it becomes much harder to spot.

“The best way to protect your property is to be aware of the risks and ensure you can identify knotweed at different times of the year. If you do have knotweed on your property, it’s wise to act immediately to treat or remove it before it has the chance to spread further. With professional assistance knotweed can be dealt with and the value of a property largely restored. If you’re buying or selling a property, consider instructing a Japanese knotweed survey to check for any sign of the plant on the property and its surroundings.”