The one plant that could prevent your home from selling.

Not all of us are horticulturists or careful conservers of our gardens, so we often have the odd plant or two where we have no idea what it actually is. However, there is one plant that could be lurking in the background that will make potential buyers turn and run, and that’s Japanese Knotweed.

But what is Japanese Knotweed, and why the fear?

As its name suggests, this plant is not native to the UK, it was introduced here in around the mid 19th century. It is known for being an extremely aggressive and invasive plant that can destroy anything in is path.  As it has no natural enemies, it can grow up to 20 centimetres a day.

The plant can be identified by its tall, purple-speckled, bamboo-like cane stems and heart–shaped leaves with pointed tips. The flowers on Japanese Knotweed are creamy white and appear in the summer and early autumn. In the winter the leaves turn yellow, then brown, and eventually they fall off, leaving dark brown canes.

Because of the devastation it can cause, the Environment Agency has described Japanese Knotweed as “Indisputably the UK's most aggressive, destructive and invasive plant".

A recent poll carried out by YouGov and Japanese Knotweed removal specialist Environet UK found that 78% of potential buyers would be put off purchasing a property if they knew that Japanese Knotweed was present in the garden.

Did you know that, if present, it is your legal responsibility as a homeowner to stop it from spreading? If not, you are among the 49% who in the poll also didn’t know that it was their legal responsibility. The poll found that nationally, 75% of people were aware of the plant, but that rose Wales to 95%.

“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,” said Mark Hayward, Chief Executive of NAEA Propertymark.

What if you have knotweed?

Not only can this plant devalue your property, and put off potential buyers, it is also mentioned in the Anti-Social, Crime and Policy Act. It is not illegal to have Japanese Knotweed on your land, but it is if it spreads to your neighbours. And as this plant is so evasive, getting rid of it as quickly as possible should be a priority.

It is notoriously difficult to eradicate, as methods such as digging it up and burning can actually encourage growth. Chemical herbicides are required, and as it’s invasive it must be disposed of at approved sites.

It is recommended that you use a specialist to ensure that the treatment is administered correct;y and thoroughly, as if even the smallest root survives it will regrow at a faster rate. There are several companies who can provide this service for you, including Japanese Knotweed Removal Wales, based in Cardiff.

For more advice on what could be devaluing your property, contact your local Bidmead Cook branch.