About Japanese Knotweed

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We measure ourselves using KPIs for each stage of the process and we believe we are the best!

    Japanese Knotweed history

    Japanese Knotweed was first brought into the UK to feature in Victorian ornamental gardens. It was then used to stabilise embankments, particularly on railways and canals which spread it far and wide in industrial South Wales.

    Japanese Knotweed develops a huge and highly vigorous root system or rhizome which acts as both an energy store and a means to spread. The size relationship between the rhizome and the visible Japanese Knotweed plant can be compared to an iceberg and the tip. Homeowners and developers often spread the rhizome without realising or through attempting to deal with the problem themselves – a 5p sized piece of rhizome can re-grow into a new infestation, creating a much greater area of Japanese Knotweed.

    What Does It Look Like?

    They range from red to green in colour with hollow, cane like stems. These can grow from 5 feet to sometimes 10 feet in height. The leaves are described as almost “heart shaped” and grow in an opposing or ‘every-other’ pattern along the stems.

    In early autumn the weed will produce a white flower and, as the winter months draw in, it will lose these flowers and the leaves, to leave the cane like stems which will remain for some months or even years.

    The Physical Impact of Japanese Knotweed

    Japanese Knotweed can be an extremely damaging plant. We’ve seen Japanese Knotweed growing through tarmac, lifting paths, cracking concrete, …damaging underground drainage and, most importantly, resisting and sometimes even thriving on all untrained attempts to get rid of it. 

    Being an invasive species, native to Japan, many of the native insects and fungi that normally attack the plant are not living here in the UK. After being here for over a hundred years, there is still nothing in the UK’s ecosystem that will naturally keep this invasive and destructive weed under control. 

    People often forget about the effect of Japanese Knotweed on gardens; as well as damaging buildings, it can overwhelm even the most expensive gardens by out-competing everything in its path. Remember this weed is non-native and is extremely hardy to our insects and fungus’.


    We measure ourselves using KPIs for each stage of the process and we believe we are the best!

      Japanese Knotweed Impacts on Property Sales, Development and Construction.

      Despite Japanese Knotweed being a highly invasive and damaging plant, many people don’t realise it will cause them a problem until it’s too late. Often not until it’s been picked up on a mortgage or ecology survey on the property or land they are buying, selling or developing. When Japanese Knotweed is found on or within 7 metres of a property, sales are usually delayed and can sometimes fall through because mortgage companies need the assurances only companies like us are certified to give. 

      When buyers and sellers are in “a chain”, sales can fall through “along the chain” due to uncertainty and high levels of anxiety caused by delays. 

      Construction companies or developers can sometimes find that planning permission involves additional costly conditions, less available space on-site followed by difficulties in selling the final buildings. When construction programmes become stretched, costs can spiral upwards as subcontractors are delayed and add extra costs for their time. 

      At Clearsafe Knotweed we have heard of land-owners abandoning their plans and selling up at a reduced cost and have known construction companies to lose their contracts because the client can no longer afford the build.

      WE ACT FAST!

      We measure ourselves using KPIs for each stage of the process and we believe we are the best!

        The 4 Stages of Japanese Knotweed Growth

        WE ACT FAST!

        We measure ourselves using KPIs for each stage of the process and we believe we are the best!

          Media Scare Stories

          You may have seen or heard some of the irresponsible stories in the media and online about what Japanese Knotweed can do and how it’s impossible to kill, which can unnecessarily worry potential buyers and sellers. This can be put down to a lack of knowledge and experience with the weed, journalistic licence and people having opinions. At Clearsafe Knotweed, we use facts and experience. Don’t read and listen to opinions, call us to review it for you.

          We know that Japanese Knotweed is just a plant, albeit, an extremely vigorous and aggressive plant that can spread incredibly quickly and easily if the correct guidance is not followed.

          In most cases, Japanese Knotweed can be treated and killed effectively and without the need to dig up your garden or land.

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