Japanese knotweed is a notoriously difficult plant to eradicate and as a result, it has become a major cause of concern for homeowners, property developers and mortgage lenders. As a non-native species to the UK, it lacks the natural brake on its spread provided by native plant species and can easily grow out of control, disrupting ecosystems and causing damage to roads, drains, buildings and structures. As a result, it is regarded as an invasive species and regulated by legislation with mortgage lenders refusing to lend on properties where knotweed is identified.
Despite being an attractive plant, japanese knotweed specialists (Fallopia japonica) can pose serious problems for homeowners and gardeners. The plant out-competes our native plants and, with no natural brake on its growth, can rapidly take over wild areas and neighbouring gardens. Its rhizomes can also break through hard surfaces and enter buildings and other structures, causing significant damage. This is why it’s a legal requirement to declare the presence of knotweed when selling a house, and lenders will require homeowners with a known infestation to submit a management plan for its eradication.
While small clumps can be controlled by digging or spraying with weedkiller, larger infestations are more challenging. Knotweed is very persistent and requires a long-term, multi-staged treatment programme to provide effective control. For this reason, it’s often best to enlist the services of professional contractors accredited by a recognised industry body such as the Property Care Association. In addition to providing risk assessments and management plans, these companies can offer an Insurance Backed Guarantee to ensure complete eradication.
A Japanese knotweed survey will identify the location and size of the weed, allowing you to make an informed decision on your next steps. For large weed infestations, professional contractors can provide excavation and removal services, which are usually guaranteed to eradicate the weed for good.
In the UK, Japanese knotweed is classed as a Schedule 9 invasive species and so must be removed from sightlines on public or private property by law. This includes roadsides and railway embankments where it has become established. A reputable contractor will be able to advise on the correct method of removal and disposal, which can include burial or incineration.
The plant is also classified as a controlled waste and it’s illegal to add it to your home compost or council-run garden waste bins. As a result, you will need to dispose of it at a licensed landfill site. The Royal Institution of Chartered Surveyors has worked with the Property Care Association to create the Invasive Weed Control Group, which provides a register of vetted specialists. If you’re concerned about the risk of Japanese knotweed on your property, contact a PCA accredited specialist like PBA Solutions to arrange a survey and management plan. You can find one by visiting the Invasive Weed Control Group’s website.