SEO: Bromley and Lewisham highest in London for Japanese Knotweed

Data from environment invasive plant specialist Environet has revealed London’s Japanese knotweed hotspots for 2024, with Greater London the third worst affected location in England after Bristol and Merseyside.

South east London is the most severely affected region of the capital, with 850 known infestations, followed by the south west with 622.

Data based on an interactive online tracker, which updates sightings reported by staff members and members of the public, revealed that there have been 60,000 known cases of this infesting plant across the UK.

South east London is the most severely affected region of the capital, with 850 known infestations. (Image: Environet) According to data, Bromley and Lewisham were among some of the boroughs with the highest numbers of cases in 2024.

Bromley was revealed to have the 4th highest number of cases with 180, followed by Lewisham in 6th, based on data from sightings calculated along with borough size.

Among the highest boroughs were Tower Hamlets with 300 followed by Wandsworth with 210.

According to data, Bromley and Lewisham were among some of the boroughs with the highest numbers of cases in 2024. (Image: Environet) Here’s the full list:

• Tower Hamlets - 300
• Haringey - 241
• Wandsworth - 210
• Bromley - 180
• Brent - 172
• Lewisham - 170
• Lambeth - 162
• Barnet - 159
• Camden - 155
• Croydon - 151

According to data, Greater London is the third worst affected location in England with a total of 3,592 incidences of Japanese knotweed, equivalent to 2.29 incidences in every square km.

Japanese Knotweed is an invasive non-native plant that can grow up to 7ft tall and root itself deep in the ground, which can affect the foundations of your home and make it difficult to sell.

Japanese Knotweed is an invasive non-native plant that can grow up to 7ft tall and root itself deep in the ground. (Image: Environet) This plant is known to spread more prevalently in areas that are highly developed, due to the movement over large qualities of soil during building works, and is estimated to cost the UK economy nearly £250 million a year.

Although it is not illegal to have knotweed growing on your land, legal issues can happen when it’s allowed to spread across property boundaries and when sellers fail to declare it to buyers.

During the winter months the plant will die back as temperatures continue to drop, sending the plant into its dormant winter phase.

However, the plant will re-emerge next spring, meaning that autumn and winter is the ideal time to excavate it when the garden is not in use.

Autumn and winter is the ideal time to excavate it when the garden is not in use. (Image: Environet) Emily Grant, director of Environet, said: “Japanese knotweed is rife across the capital, and anyone buying or selling a property in London’s hotspots should be extra vigilant for signs of the plant. Knotweed is easily identifiable during summer, but it’s perennial 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.”