Dealing with knotweed yourself

What not to do

Do not cut, strim, dig or mow knotweed, and do not compost it. Fragments as small as 1 cm can regrow, so every cut spreads the problem. Do not put it in a green waste bin: cut knotweed is controlled waste.

Do not burn it on site unless you have an Environment Agency D7 exemption.

Confirm it first

Many plants are mistaken for knotweed. Use our guide to identifying Japanese knotweed, and send a photo to a PCA or INNSA surveyor if you are unsure. Treating the wrong plant wastes time, and the wrong approach to the right plant spreads it.

Herbicide: slow, but legal

It is legal to treat knotweed on your own land with a herbicide, and the PCA says it is the most common homeowner route. Glyphosate control needs at least three growing seasons, with regular applications and monitoring. Follow the product label, keep spray off other plants and avoid watercourses.

Expect regrowth, and keep notes of the dates you treated. The RHS calls professionals the easiest and most effective way.

Dealing with waste

Cut knotweed and soil that contains rhizomes are controlled waste. Under the Environmental Protection Act 1990 duty of care, they must go with a registered waste carrier to a permitted site, with waste transfer notes. Hertsmere Borough Council, among others, tells residents never to use green waste bins.

If you must move any soil, keep it on site and covered, and ask a specialist how to handle it before digging for a patio, a drain or a fence.

What the law says

Having knotweed is not an offence, but under section 14 of the Wildlife and Countryside Act 1981 it is an offence to plant it or cause it to grow in the wild. Councils or police can issue a community protection notice if it has a persistent, detrimental effect on the community, and failing to comply is an offence.

If soil is moved off site, it is controlled waste and needs a registered waste carrier and a permitted site.

Protecting yourself and your neighbours

Keep children and pets away from the stand. Do not let tools, boots or machinery carry plant fragments off the affected area, and wash them down on the spot. If knotweed spreads onto a neighbour's land, they may bring a private nuisance claim, and RICS notes that such claims are a risk. Tell your neighbour early and share the plan.

Why DIY can cost you a sale

DIY herbicide gives no insurance-backed guarantee. On the TA6 form you must disclose knotweed on the property or within 3 m of its boundary. A buyer's lender will usually want a professional management plan with a guarantee.

If you plan to sell or remortgage, start with a specialist. See what removal costs and the specialist page.