HOMEOWNERS can now sue neighbours if Japanese knotweed ends up on their land, following a landmark court ruling.

Two home owners in Wales sued after Japanese knotweed spread into their gardens from a site owned by Network Rail. The court ruled in their favour.

In the landmark legal case, Stephen Williams and Robin Waistell, who own two adjoining bungalows in Maesteg, south Wales, made a claim against Network Rail, which owns the land immediately behind their properties.

Nic Seal, managing director of Environet, said that the pest plant puts property owners at rick of legal action from neighbours.

He explained that if left untreated, Japanese knotweed will grow rapidly, by up to 10cm a day during the summer months, pushing up through cracks in concrete, cavity walls and drains and causing damage to property.

The longer it is left, the further its underground root system will spread and the more costly it will be to tackle.

“It’s not just about protecting one’s property from damage and decreased value, it is also about protecting oneself from the risk of being sued if the knotweed is allowed to spread,” Mr Seal added.

The good news is that Japanese knotweed can be treated.

Chartered surveyor Philip Santo, director at Philip Santo & Co, says it presents a serious financial risk.

He said: “The financial consequences of concealing or not declaring the presence of Japanese knotweed during a sale can easily run into tens of thousands of pounds, so it is just not worth taking the risk.”