How Much Does Japanese Knotweed Herbicide Treatment Cost?

Here at Japanese Knotweed Removal, our herbicide treatments start at £95 (plus VAT) per application. Depending on your requirements, we can either provide a free basic survey and report or a specialist survey and report (which is required by most lenders).

Successful knotweed herbicide treatments can take multiple applications over several years. We typically recommend a three-year treatment programme with a two-year monitoring period. This service starts at £1,395 for an area of up to 25m2 depending on the level of contamination, distance to be travelled and material costs. Insurance-backed guarantees can be added as required.

Prices subject to change. Please call us on 01639 710914 to check current prices.

I’ve just had my Japanese knotweed treated with herbicide – now what?

If you’ve just had your Japanese knotweed infestation treated with a herbicide application, you may be wondering what to do next. Here are some dos and don’ts of handling your garden following a knotweed herbicide treatment to ensure success:

Do:

  • Read the management plan! If you don't understand anything, reach out and contact us; we will be more than happy to answer any questions you may have
  • Leave the Japanese knotweed alone, and allow the herbicide to work
  • Cut down the dead canes between January & February, allow them to dry out on site
  • Quarantine the area of contamination to prevent traffic spreading the plant material across your property
  • Report any new growth that is outside of the area we are treating

Do NOT:

  • Flail or mow Japanese knotweed as this will cause it to spread
  • Spread Japanese knotweed stems and crowns
  • Spread soil contaminated with Japanese knotweed rhizome (any soil that is obtained from ground within 5m of a Japanese knotweed plant could potentially contain rhizome. The rhizome is highly regenerative and will readily grow into new plants)
  • Chip Japanese knotweed material. Mechanical chippers do not kill Japanese knotweed. If you spread chipped material on soil, Japanese knotweed could re-grow
  • Add Japanese knotweed material to compost
  • Cut or trim treated Japanese knotweed plants
  • Attempt to treat the Japanese knotweed yourself with herbicide
  • Disturb the ground within 2-3m of any Japanese knotweed plant
  • Dispose of any knotweed material (including soil from within 5m of any knotweed plant or previously contaminated area) off site
  • Allow access/traffic across the area of contamination
  • Carry out any other action that may result in the spread of Japanese knotweed. If you cause/let Japanese knotweed spread, you could be guilty of an offence under the Wildlife and Countryside Act 1981