Higham and Rushden gardeners beware - you are living in a Japanese knotweed hotspot

The town has the highest infestation rate in the county

Saturday, 8th May 2021, 7:00 am

As the UK’s most invasive plant enters its spring growth phase, new figures from Japanese knotweed experts have revealed that Higham Ferrers is the top county hotspot for the pesky plant.

Using data from its interactive online tracker, Environet has created a Japanese knotweed heatmap populated with more than 54,000 known infestations of the invasive menace.

Charting the spread of the plant across the UK, the information can be used by homeowners and potential homebuyers of the local presence of knotweed and the potential risk to their property.

Sign up to our daily newsletter

The i newsletter cut through the noise

The Japanese knotweed heat map

Users can enter a postcode to discover the number of reported knotweed sightings nearby, with hotspots highlighted in yellow or red.

Mat Day, Environet’s regional director for Northamptonshire, said: “Knowledge is power when it comes to Japanese knotweed and this heatmap is invaluable to homeowners and buyers who want to assess the risk in their local area.

“Despite its fearsome reputation, with professional help, the plant can be dealt with and the value of a property largely restored.

"I’d urge anyone buying or selling a property, or homeowners wishing to preserve the value of their home, to be vigilant for signs of spring growth and check to see whether they live in a high-risk area.”

The fast-growing plant is invasive

The figures reveal there are 23 Japanese knotweed infestations within a 4km radius of Higham with Northampton second on the list with 16. Thrapston has seven and Kettering five.

Following its winter hibernation, knotweed begins to grow in March or April, depending on the local ground temperature, and can reach up to three metres by mid-summer.

Homeowners spending more time in their gardens this spring may notice purple or red asparagus-like shoots emerging from the ground and quickly growing into lush green shrubs with heart or shovel-shaped leaves and pink-flecked stems.

Japanese knotweed pushes up through cracks in concrete, driveways, patios, paths, drains and even the cavity walls of homes.

It can grow up to 10cm a day

According to Environet’s research, approximately five per cent of homes are currently affected, either directly or indirectly from a neighbouring affected property.

Japanese knotweed arrived in the UK in the 1840s, in box number 34 of 40 Chinese and Japanese plant species delivered to Kew Gardens

· Knotweed grows at the incredible rate of around 10cm a day from May until July

· When it is fully grown it can stand up to three metres tall

· Approximately £166 million is spent each year on treating the plant in the UK

· The Government estimates it would cost £1.5 billion to clear the UK of knotweed

· Japanese knotweed can lie dormant but alive under the ground for up to 20 years

· Sniffer dogs are now helping in the fight against knotweed, detecting the unique scent of its rhizome beneath the ground

· Property owners who fail to stop the spread of knotweed on their land can face fines and even a jail sentence under ASBO legislation

The public can help in the fight against knotweed by reporting suspicious plants using the heatmap’s ‘Add Sighting’ feature and attaching a photo to be verified by experts.

Click on the heat map by clicking here