Three-quarters of potential buyers would be put off purchasing a property if they discovered there was Japanese knotweed present, research claims.

A poll has found that 78% of those aware of the infamous wild plant would be put off buying a property, with 69% concerned that it can’t always be removed and more than half worried about the time or cost of getting rid of it.

Only 3% of those aware of the weed said they would not be at all deterred from buying an affected property.

More strikingly, only 49% knew that a home owner is legally responsible for preventing it from spreading from their property, and 21% are aware of the implications of allowing it to be spread on to a neighbour’s garden.

Home owners can face prosecution for allowing it to grow and fines for failing to dispose of it properly, while neighbours can also make claims for costs.

Nic Seal, managing director of Environet which specialises in removing the weed, said: “Home owners are right to be concerned about the threat posed by Japanese knotweed.

“Attempting to deal with it by cutting it down repeatedly, burning it, burying it or using common weed killers simply won’t work as the plant can lie dormant beneath the ground, only to strike again when people least expect it.

“Yet for those wishing to buy or sell a property, it doesn’t have to be a deal breaker.”

Commenting on the findings, Mark Hayward, chief executive of NAEA Propertymark, said: “Japanese knotweed has been wreaking havoc in Britain for a number of years and can  bring down the value of a property.

“Knotweed is often identified during site surveys, and while it may look small and contained, do not under-estimate the scale of the potential problem.

“It is important to have the plant treated as soon as possible to avoid further growth and prevent the property sale from falling through.”

It is, however, possible for home owners to take out an insurance policy  for just £67 that indemnifies them against the risk of knotweed appearing, even if it is present in a nearby property.