What to do if neighbour has Japanese knotweed



April 20, 2018

What to do if neighbour has Japanese knotweed

Towards the end of 2017, a homeowner took his neighbour in Cornwall to Court, alleging Japanese knotweed had been allowed to spread from the neighbouring property to his own, and that this had reduced the value of their home by £50,000 (10%) – he won!

The Court found in favour of the claimant because although it isn’t illegal to have Japanese knotweed on your property, it is illegal to allow it to spread.

July 2018 – Court of Appeal rules that landowners can be entitled to damages for Japanese knotweed

“Landowners have a measured duty of care to ensure that Japanese Knotweed does not spread from their land, following the Court of Appeal decision in Williams v Network Rail Infrastructure Limited. Even in cases where no actual physical damage has been caused, the court decision opens up claims by neighbours for loss of amenity value due to the hazard created by the mere presence of the plant’s rhizomes under their property.”

For coverage on this story from ITV News please click here

What you really want is to avoid is becoming embroiled in such a legal case.

If you would like to read about this in more detail, then follow this link to an article from The Times, February 2018:


So, what should you do?

Japanese knotweed does not need to be a deal breaker, nor a reason for hostilities over the garden fence.

Talk to your neighbour – they may not know that they have Japanese knotweed.

If you are unsure, you can email me a picture and I confirm whether or not it is.

Do your research, perhaps between you, and look for a respected company who can “eradicate” – this is important, not just “control” the Japanese knotweed.

If there is easy access to the growing canes then a dig out method may be appropriate.

If not, then a herbicidal treatment plan will be the way to go, but do be aware that this is very likely to take more than one season.

Look for a well-established firm who will have the experience and technology to eradicate the knotweed efficiently and with as little impact on the environment as possible.

Are you, or your neighbour, thinking of selling?

If so, what you will need is:

These will allow a house sale to proceed as the combination of the two will satisfy UK Mortgage Lenders.

A respected eradication company will be able to provide you with both – and this is one reason why we really wouldn’t recommend any DIY approach to removing knotweed.

Without these two documents you will struggle to raise mortgage finance.

TCM are one of a handful of UK firms that can offer the top rated A+ Insurance Backed Guarantee (IBG) underwritten by Lloyd’s – the world’s premier insurance platform.

Do feel free to email me with any questions at expert@tcmknotweedservices.co.uk