Japanese Knot weed

Japanese Knotweed

Japanese knotweed (Fallopia japonica) is a weed that spreads rapidly. In winter the plant dies back to ground level but by early summer the bamboo-like stems emerge from rhizomes deep underground to shoot to over 2.1m (7ft), suppressing all other plant growth. Eradication requires determination as it is very hard to remove by hand or eradicate with chemicals. New legislation now covers its control

What is Japanese knotweed?

Japanese knotweed is a fast-growing and strong clump-forming perennial, with tall, dense annual stems. Stem growth is renewed each year from the stout, deeply-penetrating rhizomes (creeping underground stems).


In spring, reddish-purple fleshy shoots emerge from crimson-pink buds at ground level. These grow rapidly, producing in summer, dense stands of tall bamboo-like canes which grow to 2.1m (7ft) tall. These canes have characteristic purple flecks, and produce branches from nodes along its length.

Leaves are heart or shovel-shaped and up to 14cm (5½in) in length and borne alternately (in a zig zag pattern) along the stems. The stems die back to ground level in winter, but the dry canes remain for several months or longer.

The creamy-white flower tassels produced in late summer and early autumn reach up to 15cm (6in).

More information can be found here: https://www.rhs.org.uk/membership/rhs-gardening-advice 

Under section 14 of the Wildlife and Countryside Act 1981, it can be an offence to plant or grow Japanese Knotweed. However; there is no statutory requirement for landowners to remove these plants from their property once established naturally.

Whose Responsibility Is It To Control Japanese Knotweed?

If the land is privately owned then the responsibility for the control of this weed rests with the landowner or tenant of the land.  The Environment Agency or Ashfield District Council are not obliged to control this weed on behalf of private landowners. Disputes between private landowners concerning the control of this weed are a civil matter.

Complaints concerning Japanese Knotweed growing on roadside grass verges within Ashfield District Council area or on Council owned land should be reported to environment@ashfield.gov.uk   

Alternatively: you can call the environment department by telephoning 01623 450000 and choosing option 3 for waste and environment and then option 3 for other enquiries

Japanese Knotweed growing on verges of large main roads (trunk roads) or motorways in the district, control and eradication is the responsibility of the Highways Agency and not the Council; 

New legislation

An amendment to the Anti-social Behaviour, Crime and Policing Act 2014 includes invasive non-native plants including Japanese knotweed. Here are some key points for how this affects the homeowner:

  • It is not illegal to have Japanese knotweed in your garden, but on your property you should aim to control this invasive non-native plant  to prevent it becoming a problem in your neighbourhood. If it has a "detrimental effect of a persistent or continuing nature on the quality of life of those in the locality", the legislation could be used to enforce its control and property owners may be prosecuted
  • Where problems with Japanese knotweed occur in neighbouring gardens, we suggest that you speak or correspond directly with your neighbours (who may already be taking action to control this difficult weed). These informal steps should be taken before contacting your council to talk about action under the legislation
  • Homeowners can consider control themselves for a small, isolated clump (see the Control section below). However, a specialist professional company will be skilled at control, ensure eradication and can dispose of the plant waste at licenced landfill sites

The legal situation

Buying and selling property

Since 2013, the seller is required to state whether Japanese knotweed (Fallopia japonica) is present on their property through a TA6 form - the property information form used for conveyancing. Your conveyancer or solicitor will be able to provide full legal advice, however, here is a summary:

  • If you are selling, it is your responsibility to check the garden for Japanese knotweed (bearing in mind that it can die back in winter). The TA6 form asks you to confirm whether your property is affected by Japanese knotweed and, where it is, to provide a management plan for its eradication from a professional company (see Seeking Help from the Professionals below)
  • If you are buying, the presence of Japanese knotweed will be stated in the responses to the TA6 form. This often results in your mortgage lender requiring assurances that it will be eradicated before agreeing the funds. A management plan by a professional eradication company, backed by a transferable guarantee, is usually sufficient. It is most common for this plan to be provided by the seller before the purchase is completed
  • Whether a buyer or seller, it is also worth being pro-active and checking the property for Japanese knotweed. Disputes over the identity of a plant, the failure to disclose its presence, or the lack of a management plan can result in delays, increased costs later in the buying process, or even a possible misrepresentation claim after the sale, so this approach will help avoid problems

Contact The Royal Institute of Chartered Surveyors for further information.



I Have Japanese Knot weed Coming Onto My Land From Private Land Adjoining Property.   What Can I Do?

The best solution is to co-operate with the neighbouring landowner and co-ordinate your control efforts, by sharing costs of labour or herbicide. 

Non-weed killer control

When tackling Japanese knotweed, cultural control methods pose some problems.

  • Digging out this deeply penetrating plant without professional help, even if feasible, creates problems over disposal as Japanese knotweed is classed as 'controlled waste' under the Environmental Protection Act 1990. This requires disposal at licensed landfill sites
  • Specialist Japanese knotweed contractors must be registered waste carriers to safely remove the weed from site but check first before employing their services
  • Alternatively, it can be destroyed on site by allowing it to dry before burning

 How Do I Control or Eradicate Japanese Knotweed on My Land?

  • Regular cutting or pulling will, after a number of years, eventually exhaust the rhizome and kill the plant. It is important that all cut or pulled stems of Japanese Knotweed are kept on site and disposed of by proper burning. Dense stands of Japanese Knotweed can be treated with a glyphosate-based herbicide, such as 'Roundup'. If the Japanese Knotweed is sparsely distributed, spot-treat or use 2,4-D amine, which is specific to broadleaved plants and will not harm grasses. It may take two or three years to completely kill the entire plant.
  • More effective control can be achieved if Japanese Knotweed is cut or sprayed in early summer, and then sprayed again in late summer before the winter dieback.  The use of herbicides in or near rivers, canals, lakes or drainage channels requires prior agreement from the Environment Agency.

In order to contact the Environment Agency on such matters, the national communications centre should be contacted on 08708 506 506.  Herbicide application forms can then be sent out upon request.   On no account should Japanese knotweed be included with normal household waste or put out in green waste collection schemes.

Weed killer control

It usually takes at least three to four seasons to eradicate Japanese knotweed using weed killer. Professional contractors, however, will have access to more powerful weed killer that may reduce this period by half.  When using weed killer, always follow the instructions on the pack to make effective and economic use of the product while minimising risks to people and the environment.

  •  For home gardeners, perhaps the most effective and simplest method to tackle Japanese knotweed is with a glyphosate-based weedkiller such as Roundup Tree Stump & Rootkiller. This has label recommendation for controlling Japanese knotweed, instructing it to be applied to the cut canes or a foliar spray. SBM Job done Tough Weedkiller (soluble sachet only) and Roundup Ultra also have label control for this weed
  • For home gardeners, perhaps the most effective and simplest method to tackle Japanese knotweed is with a glyphosate-based weedkiller such as Roundup Tree Stump & Rootkiller. This has label recommendation for controlling Japanese knotweed, instructing it to be applied to the cut canes or a foliar spray. SBM Job done Tough Weedkiller (soluble sachet only) and Roundup Ultra also have label control for this weed
  • Alternatively, try other tough formulations of glyphosate (e.g. SBM Job done Tough Tree Stump Killer (soluble sachet only), Doff Maxi Strength Glyphosate Weedkiller or Westland Resolva Xtra Tough Concentrate)

Glyphosate-treated knotweed will often produce small-leaved, bushy regrowth 50-90cm (20in-3ft) in height the following spring. This is very different in appearance to the normal plant and it is essential that this regrowth is treated

Bear in mind that the home gardener will not get an insurance backed guarantee without using a professional company for the control of Japanese knotweed. This may be important if planning to sell your property in the near future or if a neighbour is threatening litigation from the spread of knotweed from your property

If you do not know who owns the adjoining land or you are in dispute with your neighbour about the control of Japanese Knotweed then current legislation offers little support.

The Environmental Protection Act 1990 provides a remedy if Japanese Knotweed is causing a nuisance to private property. A private nuisance is defined as an "unlawful interference with a person's use or enjoyment of land, or some right over, or in connection with it" (Read v Lyons & Co Ltd. 1945).

A solicitor or the Citizens Advice Bureau will be able to offer advice on how to take private nuisance action against a landowner where negotiations on control or eradication have failed.

For further advice on the control and eradication of Japanese Knotweed visit:

www.environmentagency.gov.uk  or  contact the  national communications centre on 08708 506 506