The latest research, commissioned by Japanese Knotweed Specialists, part of the Grounds Care Group, has revealed that the majority of homeowners in the south west would consider concealing the presence of Japanese knotweed when selling their property.

A national survey of 3,000 homeowners, the largest of its kind in the UK, uncovered that only 42% of homeowners in the region would disclose the presence of knotweed on their property when selling, compared with a national average of 49%.

Japanese knotweed is the most invasive plant in Britain and one that can cause significant damage to buildings and infrastructure. If left untreated it can significantly decrease property values and make it difficult to sell or insure a home.

In some instances, properties with Japanese knotweed can be down-valued by up to 30% compared to properties without it. With an average property value of £329,691 across the south west, this represents a potential loss of £98,907.

Commenting on the research, managing director of Japanese Knotweed Specialists, Adam Brindle, said: “Given that knotweed can be complicated and costly to remove, it is understandable that some people would be nervous about it when trying to sell their home. However, property owners should be transparent early on about the presence of Japanese knotweed, or any other invasive species like bamboo, and take steps to eradicate it before selling.

“With tougher lending conditions and a softening housing market, it’s essential that you put your house on the market in the best possible light. A buyer and mortgage lender would much prefer a property that has had the knotweed professionally treated or excavated with a PCA-approved guarantee in place.

“Not only will this course of action prevent potentially expensive legal cases and delays, but it will also maximise the value of your property.”

Buyers and sellers should also be aware of the potential financial and legal consequences of failing to address this issue.

David Harvey of House Partnership, explains: “There are numerous examples of where the sale of a property has been significantly delayed due to the presence of Japanese knotweed, attracting further unnecessary cost and stress during the home buying process.

“However, the real cost of deliberately concealing knotweed when selling a property, lies in the potential legal ramifications of doing so. This was highlighted in a recent case where a homeowner faced legal bills in excess of £200,000 after being successfully sued by their buyer for not disclosing the presence of knotweed.

“Our advice would be to have a plan for the eradication, to be presented to the buyer, ideally before placing your property on the market.”

To avoid these issues, property owners should seek advice from professionals on how to properly disclose and address Japanese knotweed when selling a property. It is always recommended to have a professional survey and treatment plan in place before selling a property with Japanese knotweed to avoid any future problems.