1. ITV Report

Family finds house's value has halved after Japanese knotweed takes over garden

When you're selling a home, it's most people's biggest asset and you want it to look its best.

But what if your garden has been over run with a destructive, invasive and almost impossible to eradicate weed?

Our reporter Mike Griffiths meets one woman who's doing battle with Japanese knotweed.

The house in Swansea belonged 92-year-old Audrey Abraham.

She has dementia, and her family are trying to sell the house to pay for her care.

Somehow we need to tackle it or we need to auction the house at a cost that is really a lot less than what it should be fetching in her interest.

I'm her power of attorney.

I don't feel I can really let the house go without at least trying to address it to get some more money for her for her ongoing healthcare.

– Elizabeth Wakeman
  • Japanese knotweed is extremely prolific and can grow up to 20cm in just one day

  • A city the size of Swansea is thought to have about 62,000 tonnes of the plant.

  • It can cost as much as £1,000 per square metre to completely remove it.

One scientist warns people should be careful before attempting to tackle it.

There's a huge temptation to rush into controlling knotweed very quickly... often by cutting it.

The problem that you've got with that is you're not controlling the below ground part of the knotweed.

In subsequent years it's just going to grow back to be the problem that you're already encountered. And not only that... there's an obligation on those that do it down to dispose of the waste legally.

– Daniel Jones, Swansea University

Property experts say when selling a house with knotweed, having a plan in place is vital.

Firstly speak to a chartered surveyor. They will establish if you have Japanese knotweed. Bear in mind there are similar looking plants!

And if so he will put forward a chemical injection company to remove it and the eradication programme which you need when you go to sell.

– Tony Felice, Royal Institute of Chartered Surveyors

Elizabeth and her family now have to decide whether to sell the house as it is or begin to remove the knotweed.

There are no easy or cheap solutions.

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