Why is a Japanese Knotweed Dangerous


The problems with Japanese knotweeds in properties have been recently thrown in the light after the court has discussed whether landowners could file a claim if the plant made damages in their properties. When this plant is out of control, it could greatly affect the construction industry because its capable of damaging buildings, concrete, tarmac, and others. It has also been known to block construction like flood defenses and footpaths.

Aside, from breaking properties, because of the weed’s invasive nature it could decrease the value of properties or even make them unsellable. So, this could cause a huge problem for homeowners, builders, and developers alike.

The Dangers of Knotweeds

There are a lot of reasons why the plant is dangerous for most people, from the way the plant grows to how you can get rid of it could be troubling to most landowners. Now, here are several more reasons on why the plant cause danger and problems to people:

  1. Rapid Growing

Since Japanese knotweed is one of the weeds that have the fastest growth in certain countries, during its peak season in the summer it could spread in an area by almost 10cm a day. So, what seems like a small weed could unexpectedly pose a huge problem when left alone one day.

  1. Large Roots

Despite how high this plant grows, the only reason why this weed could cause so much damage to properties is that it has a wide-ranging root system. And since the plant could grow meters in different directions, it could possibly destroy the foundations of drains and buildings if it’s left to spread and grow.

  1. Quite Hard to Identify

The knotweed has few distinctive features, but it could look quite similar to other wild plants. Japanese knotweeds have large, heart-shaped leaves that are about 10cm long, and their stems look like a bamboo where flowers grow during the late summer. But like most other plants, the weeds would turn brown and its leaves would fall off.

  1. Hard to Get Rid Of

Getting rid of this plant is not as easy as you think it is. Unlike the other weeds in your back or front yard, you cannot simply pick out Japanese knotweed. Also, if not taken with care, chopping down this pant would just cause it to re-grow much faster. Therefore, in order to get rid of it successfully would take months of treatment, and would usually need to be surveyed by a professional.

  1. It Can Affect Lenders

If you’re planning on getting insurance for your property, a lender may not offer a financial loan for development or property that are swarmed with Japanese knotweeds, or even if the property had a history of it. Therefore, not only is the plant dangerous, but it could also cause a lot of huge problems for people.


Now that you know what danger and problems the weed could bring to you and your property, immediate action should be done as soon as you see the plant growing in or near your home. This way, you can prevent it from making any damages in the near future. However, if the plant has already reached full growth and needed to be terminated, you might want to consider seeking help from a professional.

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