CONVEYANCERS STILL IN A BIND WITH KNOTWEED
What buyers and sellers need to know about Japanese knotweed
How worried should conveyancing lawyers be about advising seller and buyer clients about Japanese knotweed? The answer: a lot. And for buyers and sellers, the risks are just as important to understand when entering into a property transaction.
We have seen recent lurid headlines:
‘Owner of £4m Chelsea mansion who made neighbours' homes "unsellable" with 10ft-high Japanese knotweed garden is ordered to remove the rat-infested "jungle"’ (Daily Mail, 28.04.2026).
To be fair, the issue of Japanese knotweed is much less serious than the report that a contractor has been found deceased and rotting in the basement of the above property (and condolences must go to his friends and family) – but in practical terms, it is Japanese knotweed that is far more likely to impact a property sale or purchase.
Why Japanese knotweed matters in a property transaction
If Japanese knotweed is present at a property or growing on an adjacent property, this can completely derail a sale. It is widely known that its presence can affect structures and is difficult to eradicate.
The challenge is that it can be hard to identify. Japanese knotweed dies back in the colder months but grows aggressively from spring onwards. While the RICS has suggested that the risk to structures may sometimes be overstated, this offers little reassurance to buyers if a mortgage lender refuses to lend due to its presence.
For buyers, this can mean delays, renegotiations, or even a transaction falling through. For sellers, it can impact value and marketability.
This is where taking early advice from an experienced conveyancer can make a significant difference. You can learn more about how PCS Legal supports buyers and sellers through the process via our residential conveyancing services.
Management plans and lender requirements
The situation is often easier if there is already a knotweed management plan and insurance in place. This can be provided to a lender and demonstrates that steps are being taken to control and eradicate the issue.
Without this, transactions can quickly become more complex, particularly where lenders impose strict requirements.
A key risk for sellers
There is a real danger zone for sellers if they complete a Property Information Form before instructing their conveyancer.
The current form asks whether the property is affected by Japanese knotweed, with three possible answers: yes, no, or not known. However, many sellers may not fully understand the implications of these responses.
Previous guidance made it clear that answering “no” required certainty that no rhizome (root) was present within 3 metres of the property boundary. This emphasis has reduced in newer guidance, increasing the risk of incorrect answers.
If a buyer relies on an inaccurate response, this could lead to a misrepresentation claim if Japanese knotweed is later discovered.
Seeking legal advice early can help avoid these risks. Working with a conveyancer from the outset ensures forms are completed correctly and reduces the likelihood of disputes later in the transaction.
Buying a property affected by knotweed
For buyers, the key is awareness and due diligence.
If a seller indicates they do not know whether Japanese knotweed is present, it is often sensible to obtain a specialist survey or report before exchange of contracts.
Buyers should also be aware that:
Lenders may impose conditions or decline lending
Insurance-backed treatment plans may be required
Delays can occur while issues are investigated
Having a conveyancer who can clearly explain these risks and liaise with all parties is essential to keeping the transaction on track.
It’s not just knotweed
While much of the focus is on Japanese knotweed, other invasive species such as bamboo can also cause issues.
Conveyancers are not horticultural experts and will not inspect the property, so their role is to ensure that risks are properly identified and that clients are advised to obtain specialist input where needed.
Why early legal advice matters
The continued push for upfront information in the conveyancing process has clear benefits, but only where buyers and sellers take legal advice early.
Too often, clients delay instructing a conveyancer in an effort to save costs at the start of a transaction. However, issues such as Japanese knotweed highlight why early involvement can prevent much larger problems later.
At PCS Legal, we regularly support clients with identifying and managing risks early in the process, helping transactions proceed as smoothly as possible. In fact, our Express & Fast Move services expedite the conveyancing process when we’re instructed early, working on any issues and required documents as soon as possible.
Get in touch
If you are buying or selling a property and would like guidance on potential issues such as Japanese knotweed, our experienced team is here to help.
📞 01268 590003
📧 quotes@pcslegal.co.uk
You can also explore our residential conveyancing services to understand how we support clients at every stage of the transaction.
With offices across Essex and beyond, including Basildon, Ongar, Rayleigh, London, Wickford, Harlow and Frinton-on-Sea, PCS Legal supports home movers across the region and throughout England and Wales.