Chemical Knotweed Treatment

Find out about our professional herbicide treatments for Japanese knotweed

The use of chemical herbicides is usually the least intrusive and most cost-effective Japanese knotweed treatment option.

Our “3-step Japanese knotweed herbicide treatment system” allows the herbicide to reach both the tall Japanese knotweed foliage and the root system that can grow up to 3m below the surface.

Considerations for Chemical treatment

A major concern when using herbicide is whether or not the Japanese knotweed is near a water source. This will dictate the types of chemicals that can be used in accordance with regulations from The Scottish Environment Protection Agency (SEPA) and the Property Care Association (PCA).

Another consideration with herbicide is the fact it typically needs 3 to 5 annual applications before becoming effective. By organising a Japanese knotweed survey, a surveyor can inspect your property and advise the best Japanese knotweed treatment method.

Other things that need to be considered before applying herbicide include:

  • The size of the growth and the extent of the rooting system
  • If there are other plants nearby that may be affected by the spray

Our professional Japanese knotweed herbicide treatment system

Step 1. Herbicide spray

Our broad-based Japanese knotweed herbicide spray can reach the highest Japanese knotweed foliage. All herbicide spray methods are applied using a "knap-sack-back-pack" unit set at 1 bar of pressure and fitted with an even flat fan nozzle for a coarse droplet to minimise drift. This method makes sure that only the targeted Japanese knotweed is killed, allowing native plant species in the area to thrive once more.

Step 2. Stem injection

Innovative and dynamic, the stem injection is applied through an injection gun that delivers a calibrated dose of herbicide directly into the bottom node of the stem. This ensures the herbicide is delivered to the crown and root system (rhizome) with no other native species being affected.

Step 3. Hand sponge

Perfect for areas where herbicide sprays may unavoidably affect other plants and foliage around the Japanese Knotweed growth. This simply involves sponging the knotweed leaves and stems with herbicide to ensure other plants and foliage are not affected.

Japanese Knotweed herbicide treatment timescales

A Japanese Knotweed herbicide treatment program will generally take anywhere from 1-4 growing seasons to be 100% effective. It really depends on the extent of the knotweed issue, the type of herbicide treatment required and the considerations listed above. That said, after a professional Japanese knotweed survey one of our experts can usually estimate the time it will take to fully eradicate the knotweed problem.

However, if you are trying to sell your property, our 10-year Japanese knotweed guarantee is effective from day 1 of the treatment process. Meaning you may be able to sell your property before the treatment is finished.

Contact us about Knotweed herbicide treatment

If you suspect you have Japanese knotweed on your property, call Wise Knotweed Solutions today or click to contact your local branch.

You can also contact the team online by clicking the button below.

Contact Wise Knotweed Solutions