Knotweed and the Law: Your UK Legal Obligations

Japanese knotweed is not illegal to have on your property. It is illegal to allow it to spread, to dispose of it incorrectly, or to ignore it once a neighbour has formally notified you of encroachment. Three pieces of UK legislation govern the plant, and most of the offences London property owners commit are unintentional.

1. Wildlife and Countryside Act 1981

Section 14 makes it an offence to plant or otherwise cause Japanese knotweed to grow in the wild. This includes dumping garden waste containing knotweed in a hedgerow, a skip not licensed for it, or a council green-waste bin.

2. Environmental Protection Act 1990

Knotweed-contaminated soil is classified as controlled waste. Removing it from site requires a licensed waste carrier, a Duty of Care chain of documentation, and disposal at a permitted landfill. Fines for non-compliance reach £5,000 per offence in the magistrates' court and are unlimited in the Crown Court.

3. Anti-Social Behaviour, Crime and Policing Act 2014

Local authorities can issue Community Protection Notices to property owners who allow knotweed to encroach onto neighbouring land. Failure to comply is a criminal offence carrying fines up to £2,500 for individuals and £20,000 for companies.

Civil Liability

Separately from the criminal law, English common law allows neighbours to sue for private nuisance where knotweed has spread onto their land. Damages typically cover treatment costs, residual diminution in value and legal fees.

How to Stay Compliant

Commission a survey, follow a written management plan, use only licensed waste carriers, and respond promptly to any neighbour notification of encroachment. With those four steps, you cannot fall foul of any of the above legislation.