Guide
Japanese knotweed treatment cost: published UK herbicide plan prices
Updated
A herbicide treatment plan for Japanese knotweed costs a median of £1,900 across the seven UK specialists that print a starting price on their own page, with a spread of £1,500 to £3,000, read in October 2026. GOV.UK says it usually takes at least 3 years to treat, so a plan runs over several seasons.
The published prices
| Specialist | What the price covers | Published price |
|---|---|---|
| Knotweed Services | Herbicide treatment over 5 years, domestic | from £1,500 |
| Weed Control UK | Herbicide treatment programme | from £1,500 |
| Taylor Weed Control | Three-year treatment and two-year monitoring | from £1,595 + VAT |
| TP Knotweed | Herbicide programme, residential garden | from £1,900 + VAT |
| Japanese Knotweed Ltd | 10-year plan with insurance-backed guarantee | from £1,991.90 + VAT |
| JBB Knotweed Solutions | Herbicide treatment plan | from £2,500 |
| Environet | Professional treatment programme | from around £3,000 + VAT |
Sources: Knotweed Services, Weed Control UK, Taylor Weed Control, TP Knotweed, Japanese Knotweed Ltd, JBB Knotweed Solutions and Environet (every row, with its source).
What a treatment plan includes
GOV.UK says spraying or injecting the stems with approved herbicides can stop knotweed spreading, that it usually takes at least 3 years, and that anyone spraying needs a certificate of competence for herbicide use or must work under a certificate holder's supervision. The rhizome can stay dormant for years and regrow if the soil is disturbed, which is why plans include monitoring visits after the last spray.
The guarantee
Mortgage lenders often ask for a management plan backed by an insurance-backed guarantee. Of the published prices, Japanese Knotweed Ltd's from £1,991.90 + VAT already includes a 10-year plan with one, and TP Knotweed publishes insurance-backed guarantees from £95.20 per property, so check whether a quote includes the guarantee before comparing it with another.
What moves the price
- The area of the stand and how many stands there are.
- Whether a sale or mortgage needs a guarantee and a lender-ready plan.
- Access, and whether the stand is near water or a protected site, which brings extra permissions.
- Travel to the site.
Published figures are what each specialist advertises on its own page, read through our fetch box on the date shown. A 'from' price is the firm's floor, not the price of your plan.