Japanese knotweed
The lender asks a knotweed question and the beds were bare on a winter visit. What has winter bareness not proved?
Not the absence of knotweed. Bare beds on a winter visit have not proved the lender's question one way or the other. Japanese knotweed dies back in winter, so a bed with no canes that day can still hold rhizome. The survey saw the season it was given. It did not see a summer's growth, and it did not excavate the beds. Winter bareness is a description of the surface. It is not a clearance certificate, and it should not be typed into a lender form as proof the ground is clean.
Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.
What is the fuller explanation?
Lenders ask about knotweed because the plant is a property issue, not because a surveyor can settle it by glancing at empty soil in January. RICS reporting is about what is known and what is visible, including growth that may be off site. Visibility fails when the plant is dormant. A bare bed is compatible with no knotweed, and it is compatible with knotweed that has died back. The visit cannot tell those apart. Say what was seen, and say that winter hid the test.
Do not answer the lender from the season. If you know of treatment, produce the papers and check they name this garden. If you know of nothing, do not convert ignorance plus bare soil into a no. GOV.UK still expects live concern about spread where knotweed is present. The survey should not be edited so a winter photograph becomes a warranty. Ask the surveyor what the season stopped them seeing, and give the lender that limit rather than a cleaner answer than the visit earned.
What should you ask your surveyor?
- What date was the visit, and were you relying on dormant beds?
- Did you see crowns, cut canes, or only bare soil?
- Which lender question would be going beyond what the season showed?
What are the typical next steps?
- Tell the lender the beds were bare in winter, not that knotweed is absent.
- Do not treat the survey as a clearance certificate.
- Produce treatment papers if they exist, and check the address.
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Also asked about this
Can a winter survey honestly tick that there is no knotweed?
No. Bare beds have not proved absence. Dormant rhizome would not show as canes that day, so winter bareness is not a clearance.
Does summer growth elsewhere in the street answer this garden?
No. Another garden is not this soil. The lender's question is about this property, which winter did not prove clear of knotweed.