Why is Japanese knotweed so bad?
Learn which three traits make Japanese knotweed such a threat and what you can do if you have discovered knotweed near your property.
One of the questions we are most frequently asked is “Why is Japanese knotweed so bad?” It is one of the UK’s worst invasive species, but it didn’t always have this reputation. The Victorians celebrated knotweed for its Oriental aesthetics and bamboo-like appearance. They shared cuttings among one another and disposed of unwanted plants carelessly.
The spread of the plant continued through soil movement in the construction industry and was undetected until well into the nineteenth century, giving it plenty of time to get a firm grasp on UK soil.
So why do homeowners, business owners, and local authorities now spend millions every year trying to eradicate it? Why is Japanese knotweed so bad?
Why is Japanese knotweed so bad?
1. Knotweed can grow in a wide range of conditions
Knotweed’s strong, robust plant structure means it can thrive in a wide range of growing conditions. Soil pH or salinity has little impact on the growing rate of the plant, and it can survive temperatures as low as -35°C.
In built-up areas with limited soil availability or poor lighting it can exploit gaps in concrete and brick, taking root and causing structural damage to driveways, roads, and property foundations.
This can seriously affect the value of your home and influence your chances of getting a mortgage accepted.
2. It can grow up to 10cm a day in the summer
Japanese knotweed can grow at a phenomenal pace, reaching speeds of up to 10cm a day during the summer. As a result of this, it can quickly and easily overwhelm competitor plants in the near vicinity and threaten properties by taking root within foundations.
Individuals with Japanese knotweed on their premises have a legal responsibility to prevent the spread of the weed into neighbouring locations. Failure to stop the spread of Japanese knotweed onto neighbouring properties is an offence that can result in an Antisocial Behaviour Order (ASBO) and a fine of up to £2,500.
3. Its roots can extend up to 7 metres outwards
Japanese knotweed grows extensive root systems up to three metres deep and up to seven metres in all other directions. This makes removing the roots a difficult and labour-intensive task.
If any small portion of the plant is left in the soil, even a few inches, it can very quickly re-sprout. Only killing the entire underground root system will guarantee the eradication of the plant.
What to do if you discover knotweed on your property
Japanese knotweed is classed as “controlled waste” under the Environmental Protection Act of 1990 and must only be disposed of into licensed landfill sites to stop further spread.
Any attempts to remove knotweed should therefore be carried out by licensed professionals. A range of treatment options are usually available for controlling or permanently eradicating the knotweed from your premises.
Don’t be threatened by Japanese knotweed. Disposing of this plant is not an easy task but with proper treatment and professional help it can be permanently removed from your premises.
If you suspect you have knotweed and are uncertain or anxious about how to proceed, we can come and take a look for free – no obligations. If you enquire now, we can be with you in less than 48 hours. We’re here to help.