Japanese knotweed distribution

Environet estimates that approximately 5% of homes across the UK are currently affected by Japanese knotweed, either directly or neighbouring an affected property, typically impacting property prices by around 5% -or up to 10% in severe cases. Search our heatmap by postcode to see if your property is in a high-risk area.

Exposed™: The Japanese Knotweed Heatmap is an interactive online heatmap of Japanese knotweed in the UK. Designed to inform homeowners and homebuyers of the local presence of knotweed and the potential risk to their property, the Japanese knotweed UK map is generated from over 57,000 known infestations, with new sightings added daily.

Although your area may be low risk, Japanese knotweed can actually be found in every 10 square km patch of the UK

Don't take a chance when buying or selling a property. Protect your investment.

What does Japanese knotweed look like?

Japanese knotweed stems

New red shoot appears in spring resembling asparagus

Japanese knotweed leaves

Distinctive shield shaped leaves with alternating sub-branches

Clusters of attractive white flowers in summer

In winter the yellowy orange leaves will eventually turn brown

Need a professional assessment on whether a property is affected by knotweed?

If you’re buying or selling a property, you’ll want to find out whether or not it is affected by knotweed. As a seller, you must be certain before completing the TA6 form, which, if answered incorrectly, could leave you exposed to a legal case in the future.

Our JustCheck™ surveys are the perfect solution for buyers and sellers alike. 

Our expert surveyors will check the property for any sign of knotweed and where none is found or suspected we’ll provide a 5 year warranty to cover the cost of treatment in the unlikely event knotweed should appear later.


Map of Japanese knotweed in Sheffield

Here are the top 6 reasons why Japanese knotweed should be removed from a residential property:

Is your property affected by Japanese knotweed?


Protect your assets

Knotweed will make it more difficult to sell an affected property, impacting its value by an average of 10%. Half of would-be buyers will walk away from a property known to be infested with knotweed. Sellers are required by law to disclose the presence of knotweed – if they don’t, they risk an expensive misrepresentation claim in the courts.


A growing problem

Knotweed is programmed to grow. Its underground rhizome system extends year on year, steadily affecting more ground. It’s a problem that simply won’t go away on its own, so the sooner it’s tackled the better.


Nuisance Neighbours

Knotweed does not respect property boundaries and those who allow it to spread also diminish the value of their neighbour’s property. This can lead to neighbour disputes and costly civil claims under private nuisance legislation.



Knotweed can and does cause damage to property. Perhaps not as bad as some might make you believe, but don’t under-estimate the damage the plant can wreak.


DIY Disasters

notweed and building or landscaping projects don’t mix! If you want to add that conservatory, summer house or home office pod to the garden, tackle the Japanese knotweed first. 


The heavy hand of the law

And for those who are still not convinced, be aware that an injunction or Community Protection Notice, otherwise known as an ASBO, can enforce people to act to remove knotweed from their property.

Prevent costly damage to your property

Want to know how?

Japanese knotweed present on a residential site

Residential solutions

Digger on a commercial site

Commercial solutions

illustration of a digger removing Japanese knotweed

Learn more about how it was built and how it can help

Heatmap details

This tool is an invaluable source of information to property professionals involved in transactions such as chartered surveyors, conveyancing solicitors and estate agents. Where a high number of knotweed sightings appear nearby, homebuyers may wish to instruct a Japanese knotweed survey to check the likelihood of the property they intend to buy being affected or at risk of encroachment from infestations in the vicinity.

Report sightings – join the fight against Japanese knotweed

You can join the fight against Japanese knotweed by reporting any sightings of Japanese knotweed online, using your smartphone, tablet, or desktop computer. We’ve made it really simple, it takes just a few seconds. Click “Add Sighting”, zoom in on the satellite view and click the central position of the knotweed location. You’ll only be asked to define the size of the infestation, some further information is requested but is optional. No sign-in or passwords are required.

Wherever possible we’ll verify new sighting reports to keep the Heatmap both current and accurate.

Start fixing your invasive plant problem today by requesting a survey

Need help or advice?

Call or email to speak to the specialists


Our team of experts is available between 9am and 5:30pm, Monday to Friday to answer your enquiries and advise you on the next steps

Want a survey?

If you already know you have an invasive plant problem, you can request a survey online in less than two minutes by providing a few brief details. A member of the team will swiftly come back to you with further information and our availability.

Need quick plant identification?

Simply upload a few images of your problem plant to our identification form and one of our invasive plant experts will take a look and let you know, free of charge what you are dealing with. We’ll also be there to help with next steps where necessary. 

Contact our team of experts today