Japanese Knotweed Treatment Cost

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Japanese knotweed is a highly invasive, fast-growing weed, which left unchecked can cause extensive damage. That is why homeowners, local authorities, businesses and developers are advised to act at first sight of the plant to halt its destructive course.

Aside from the costs of damage to walls, pavements, foundations, drains and more, there are costs involved in removing the Japanese knotweed itself, which can often run into many thousands of pounds. Japanese knotweed treatment costs will vary from site to site, depending on a number of factors, including the extent of the infestation, type of treatment required, and the speed at which the knotweed needs to be eradicated.

Each scenario we handle is different and you will receive a bespoke quote, but to get an idea on the costs and the treatment options, read on…


Japanese knotweed growth

Japanese knotweed is extremely hardy and can grow practically anywhere. It has an extensive network of roots which can grow up to 3 metres down and spread out around 7 metres from its source.

The plant can grow back from the tiniest piece of root material, so it is vital that this is completely removed from the soil to ensure that the plant doesn’t re-establish itself on the site. With a growth rate up to 10 cm per day during spring and summer, Knotweed can very quickly take hold of a site, requiring professional help.


Japanese knotweed treatment

So how much does it cost to treat Japanese knotweed? As every Japanese knotweed situation is different, it is difficult to put an exact measure on the cost of removal. Much depends on how well established the infestation is, the location (e.g is it near to water?), and the method required for its removal.

However, the following should give you an outline indication of how much it might cost to treat Japanese knotweed on your site:

Small domestic property – would normally be considerably less than an extensive invasion on development land. A typical domestic residential property using a chemical treatment programme would cost in the region of £3,000 + VAT and with the option of a 10-year insurance backed guarantee.

Small commercial site – using chemical treatments alone might cost £5,000 + VAT with the option of a 10-year insurance backed guarantee. 

Larger commercial/development site – often require a speedier solution using mechanical methods, such as excavation and the removal of infested soil and ground materials. This will be far more expensive than chemical treatment methods. Costs typically start from around £7,000 + VAT including a 15-year in house guarantee and the option for a 10 year insurance backed guarantee.


Factors impacting on the cost of Japanese knotweed removal

Costs of Knotweed will be dependent on a number of factors including:

  • Size of area to be treated
  • Ecological restraints (e.g proximity of waterways)
  • Estimated time of completion
  • Type of treatment (chemical, mechanical or other, or a combination of methods)
  • Method of disposal (burial, off-site disposal)
  • Topography
  • Depth of water table
  • Ease of access to site

Japanese knotweed treatment costs include the services of the specialist as well as the charges for equipment and herbicides. Chemical treatment is the most cost effective method for control, but can take up to five years of repeat treatments before it is fully eradicated. The method of chemical treatment, whether using spraying of foliage or stem injection, can also have a bearing on costs.

If you choose to have Japanese knotweed removed by excavation, you need to take into account not only the costs of any mechanical equipment, but also the costs of disposal. Since the plant is classified as controlled waste, it must be transported by a licensed carrier and disposed of at a licensed landfill site, and this can be costly.


Japanese knotweed treatment plan costs

Japanese knotweed treatment plan costs may at first seem high, but compared to the costs of doing nothing, then it really is a no-brainer. Acting as early as possible will ensure that the spread is minimised and damage caused by the plant will be kept to a minimum.

Having your Knotweed problem dealt with also ensures you avoid any potential legal implications and costs should the Knotweed have spread in future from your property to adjoining properties.

While Japanese knotweed treatment can be costly and time-consuming, leaving it untreated can quickly outgrow the cost of removing it. The cost of treating or removing Japanese knotweed is minor when compared to the potential damage the plant could cause to buildings and other underground utilities.

For more information on the treatment of Japanese knotweed, get in touch with us. We can provide you with a quote and help with identification, management and removal of the weed. With over 15 years of industry experience and a 10 year insurance backed guarantee for both private and commercial clients, you can be confident your knotweed problem has been eradicated for good.