japanese knotweed on house

Expert Advice on how to Sell Your Property with Japanese Knotweed

Japanese Knotweed is a highly invasive weed. In fact this is considered one of the most dangerous invasive species in the country because it grows at an exceptional rate, while causing serious damage to gardens, properties and more. This can make selling a house with Japanese knotweed next to impossible.

This plant can grow over nine feet in only ten weeks. During spring and summer months it shoots to over seven feet in height with large fourteen centimetres leaves. When the plant first pushes through, homeowners can identify it by its red/purple shoots. The problem is that it’s not easy to get rid of and requires professional assistance to eradicate it effectively.

Can I get a mortgage on a house with Japanese knotweed?


Japanese Knotweed is causing serious damage when it comes to properties, to a point where many mortgage companies throughout the country will not authorise a mortgage of any property that has this plant species on the property. The mortgage is only approved once there is proof that the species has been eradicated effectively with limited risk of returning.

The problem is that when you find this invasive plant in your garden, pulling it out by hand, trying to dig it out or even spraying it with weed killer only fuels the fire and gets the plant to grow bigger and thicker. As you pull from the stem, it splinters and that is all it takes for the plant to grow again. Digging pushes the contaminated soil around, against enabling it to grow.

Because this plant grows stems underground as well as above ground, it spreads at an exceptionally fast rate. Finding all these stems and removing them is a massive task, which is best carried out by a professional weed control expert. The weed control expert carries out treatment over a few weeks, spraying into the stem and then eliminating the plant completely, while removing it in a safe and controlled manner.

What will Japanese knotweed do to my house?

japanese knotweed on house

Japanese Knotweed can hamper properties sales because of its fast underground stem system. The stems will find the smallest hole and find a way in, whether it’s weakened cement or a hole in a drainpipe or sewer line.

This plant can cause such damage to driveways and paths, it also hampers council roads by pushing up through cracks and crevices. As it grows is causes damage to the cement or paving, causing it to crack. As you can imagine this is a serious concern for councils throughout the country who are trying to eliminate damage to the roads making it safe for drivers.

Because the plant grows underground, pushing up stem shoots as it grows, it can be a serious concern when it comes to underground piping, such as drains and sewer lines. The plant will find the smallest crack in the piping, pushing its way through and causing damage. This can result in leaking sewer, drain and water pipes, an expense for any homeowner.

Can I sell a house with Japanese knotweed?

Japanese Knotweed has also been known to cause damage to house foundations. Now while this is rare, this invasive weed will find a weak point and make its way through as it grows. This is why it’s so important that the plant is eradicated safely and in a controlled manner, minimalizing the risk of it growing back.

Many people are under the false sense of security that during autumn the root turns brown and the plant dies. They believe that this is the time to pull it out of the ground, but they do not realise that the stem underground is still in place and able to return as spring starts. Even if you only notice this invasive plant in winter when the thick bamboo like stem turns brown, you still need to call in a professional to remove it effectively.

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