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January 16, 2025
Japanese Knotweed is the UK’s No.1 non-native invasive plant species, originally brought to the UK in the early 1900’s. It was at that time and for decades confined to private estates, but towards the 1970’s it began to spread throughout the country and is estimated in 2025 to be affecting as many as 1.2 million properties.
Japanese Knotweed is deemed dangerous partly because of its ability to grow so fast, growing up to 3 metres deep and 7 metres wide. Once a new growth sprouts from that initial growth, the spread goes on and on, far and wide. Because it can grow so fast and thickly, it tends to block the sun from getting to any other flowers lower than it, and stops sun getting to the ground. This prevents any other flowers from growing and strips the soil of nutrients, meaning the knotweed will flourish while everything around it dies off.
The solution to Japanese Knotweed for the last 30 years has been with the use of a chemical called Glyphosate. It promises to ‘control’ the Knotweed and stops its vigorous growth and spread, but never fully eradicates it and so the treatment with Glyphosate is required a few times a year.
In recent years independent studies across the world have found Glyphosate to be dangerous for animals and also for insects and micro-organisms living in the soil.
Further studies have also shown Glyphosate to be dangerous to humans and animals, and is now being linked to health issues.Glyphosate is the most used chemical herbicide across the world, but many countries are looking at reducing its use. In the UK a complete ban on the use of Glyphosate in the UK will take effect in December 2025.
In 2023, the Japanese Knotweed Agency launched the first commercial thermo-electric eradication service in the UK. This innovative method uses electricity to destroy the plant’s cell structure, effectively killing it without the use of chemicals. The treatment is safe for other plants, animals, and soil microorganisms.
Thermo-electric treatment involves applying up to 5000 volts directly to the knotweed, boiling it from the inside out and depleting its energy reserves, making it very hard to regrow. With ongoing supervision, assessment and thermo-electric treatments, the Japanese knotweed is attacked until it completely dies off and composts away into the ground.
Plants, flowers or trees are not affected by the treatment, and more so, there is no danger to animals or wildlife or to microorganisms in the soil. Thermo-electric is very targeted and there are no adverse effects and importantly no chemicals used at all, a truly environmentally friendly and true eradication service.
Thermo-electric treatment is not a one off, but typically requires several attendances which are all typically included in a 5-year or 10-year plan with guarantee, so you will typically know the plan of works upfront.
Japanese Knotweed Agency cover the whole of England and Wales, and now serve customers across Northern Ireland and Eire in 2025.
Their service is available to tenants, landlords, homeowners, businesses, land owners, and virtually anyone with a Japanese Knotweed infestation that they want to get rid of once and for all. They offer surveys to assess an infestation or where purchasing a property to see if the property is affected by Japanese Knotweed before a sale completes.
In 2022, Japanese Knotweed Agency launched the Japanese Knotweed National Register, which holds approximately 43,000 reports submitted to us, and which anyone can use by simply entering the first part of their postcode to get an idea if and how many reports we have had in a particular postcode. While the register replies on reports to us, and is not a solid indication, it does give you some idea of if and how many reports we have had to date for that postcode.
If you’re not sure if the plant you’re looking at is in fact Japanese Knotweed there is also an extensive Gallery on their website which includes what it looks like throughout the seasons to help you identify that strange looking weed or plant.
Or if you’re still unsure, they offer a free online identification service, simply send some photos through on their online webpage form here and they promise to reply within 2 hours.
March 25, 2025 
