SHORT ANSWER: Most commercially-available herbicides are ineffective when used on Japanese knotweed. Appropriate herbicides are required to get this invasive plant properly under control.
Japanese knotweed can be dealt with in several different ways, but treating the plant with herbicide is the most-used method. Herbicide application is less disruptive than excavation (which involves digging the plant up and either disposing of it at an approved landfill site or burying it in a geotextile membrane), and it's far more cost-effective as well. In general, we only recommend excavation when time is limited, e.g. when Japanese knotweed needs to be cleared ASAP so that a property sale can be finalised or so that building work can go ahead. Many sites are not suitable for excavation at all.
In most other cases, herbicide application is our preferred method for controlling Japanese knotweed - specifically, we recommend applying herbicide to the leaves of the plants. This process must usually be repeated several times over the course of a few years. A typical treatment programme comprises multiple herbicide applications over three years, followed by two years of monitoring to make sure the knotweed doesn't return.
Does Roundup work on Japanese knotweed?
Very few of the herbicides you're likely to find in your local supermarket are completely effective against Japanese knotweed. Roundup (one of the best-known brands) is a popular choice because it contains glyphosate - a systemic herbicide that has proven effective when used to treat Japanese knotweed.
However, getting Japanese knotweed under control once and for all is exceedingly difficult, even with the help of glyphosate-based herbicides like Roundup. Many homeowners have breathed a sigh of relief upon seeing the plant die back after herbicide application, only to despair when the knotweed re-emerges the following year.
This is why we recommend multiple herbicide applications, and it's also why we recommend calling in a professional instead of attempting to control Japanese knotweed yourself. Fill out our contact form or email firstname.lastname@example.org for free expert advice.
Professional knotweed treatment using specialist herbicides
Here at Taylor Total Weed Control, we offer a selection of reasonably-priced Japanese knotweed treatment plans to take care of your knotweed infestation. Our invasive species experts use specialist herbicides that are not available to the general public, and which are designed to be effective on Japanese knotweed specifically.
If there's Japanese knotweed growing near your property, call Taylor Total Weed Control on 029 2039 7554 and we'll recommend the best course of action.
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