Japanese knotweed is a highly invasive weed that can quickly take over an area, crowding out native plants and damaging property.
If you have Japanese knotweed on your property, you need to take action fast. Left untreated, this weed will continue to grow and spread.
The best way to kill Japanese knotweed is with a herbicide like Roundup. Roundup kills weeds by inhibiting their ability to produce chlorophyll, causing them to die.
- Fast action ready to use weed killer that kills the weeds and roots with visible results in 1-2 days
- Kills most garden weeds with a single application; up to 10 minutes of continuous spray when using 5 L option
- Children and pets need not be excluded from treated areas (once dry)
- The Pump N Go pressure sprayer is easily refillable, a one- touch trigger prevents hand fatique and extendable lance avoids bending.
- Degraded in the soil by micro organisms
- Fast action ready to use weed killer that kills the weeds and roots with visible results in 1-2 days
- Kills most garden weeds with a single application
- Children and pets need not be excluded from treated areas (once dry)
- Degraded in the soil by micro organisms
- Leaves no harmful residues to allow replanting
What is Japanese knotweed and why should you be concerned about it?
Japanese knotweed is an invasive plant species that originated in Asia. It was introduced to North America and Europe in the 1800s, and it has been spreading rapidly ever since. Japanese knotweed is a major problem because it grows very quickly and crowds out native plants.
It also has deep roots that can damage foundations, concrete sidewalks, and even bury utility lines. What’s more, the plant is extremely difficult to kill, and it can reproduce from even a small piece of stem or root. As a result, Japanese knotweed is considered one of the most invasive plant species in the world.
If you suspect that Japanese knotweed is growing on your property, it’s important to take action immediately. Left unchecked, the plant can cause serious damage to your home and landscaping.

How does weed killer work and can it kill Japanese knotweed effectively?
One of the most common methods of controlling Japanese knotweed is to use a weed killer. But how does weed killer work, and can it effectively kill Japanese knotweed?
Weed killers work by targeting specific plants and inhibiting their growth. The active ingredient in most weed killers is glyphosate, which prevents plants from producing the amino acids they need to grow.
When applied to Japanese knotweed, glyphosate will kill the plant and prevent it from spreading.
However, it is important to use a weed killer that is specifically designed for Japanese knotweed, as some products are not effective against this invader. With the right weed killer, you can control Japanese knotweed and keep your property safe from this destructive plant.
Several chemical herbicides are effective at killing the plant, but they must be applied repeatedly over several growing seasons to achieve complete control.
The most common active ingredient in weed killers is glyphosate, which works by inhibiting an enzyme that is essential for plant growth.
When applied to Japanese knotweed, glyphosate will kill the plant within a few weeks. However, it is important to note that glyphosate will also kill any other plants that it comes into contact with, so care must be taken to avoid harming desirable vegetation.

Potential risks associated with using weed killer to get rid of Japanese knotweed?
Japanese knotweed is a fast-growing, invasive plant that can cause serious damage to your property. While it is technically possible to kill the plant using weed killer, this approach comes with a number of potential risks.
First of all, it is important to use the correct type of weed killer, as some products are ineffective against Japanese knotweed.
Secondly, there is a risk of damaging other plants or killing helpful insects if the weed killer is not applied carefully.
Finally, it is important to dispose of any dead plants properly, as they can still spread Japanese knotweed if they are not disposed of properly. For these reasons, it is generally advisable to hire a professional to deal with Japanese knotweed rather than trying to kill it yourself.
Alternatives to weed killer for killing Japanese Knotweed
Luckily, there are a number of alternative methods for killing Japanese knotweed. One option is to physically remove the plant from the ground. This can be done by hand or with the help of a machine such as an excavator.
Another option is to smother the plant by covering it with a tarp or heavy plastic sheeting. This will block out sunlight and prevent the plant from being able to photosynthesize.
Ineffective methods for removing Japanese knotweed
One option that is reported widely to be able to kill Japanese knotweed is using vinegar and salt. Whilst these can cause the plant to become dehydrated and appear to die above the ground, it is far from dead.
Due to the rhizomes growing laterally underground it can remain dormant for up to 20 years and grow from the smallest piece. Therefore, without a proper chemical knotweed management plan, it is highly unlikely to be killed.
The same can be said for using boiling water to scald the leaves and stems of the plant, preventing them from regrowing. Realistically chemical usage is by far the best approach.
Another redundant method mentioned a lot is the practice of encouraging the introduction of other plants that compete for resources such as water and nutrients.
Again, the rhizomes of the Japanese knotweed prevent any effective method of killing it below the ground due to how deep the rhizomes penetrate the ground.
In conclusion
Japanese knotweed is a weed that can be difficult to kill and there are many herbicides on the market that claim to kill Japanese knotweed.
Some herbicides work better than others, and it may take several applications to completely get rid of the weed. If you are looking for a weed killer that will kill Japanese knotweed, you may want to try one of the following products.
Want to know more about Japanese knotweed?
Knotweed Removal aims to provide the most up-to-date information, help, and advice for YOU to make informed decisions. If you are unsure or uncertain about how to proceed, please reach out to us and we will gladly come back and advise you as best we can.
Governmental advice can be found here and the UK law covering the removal of Japanese Knotweed as stated under the Wildlife and Countryside Act 1981 can be found here.
The best means to contact us is via our email – hello@knotweedremoval.tips
Do not forget we have a library of blogs covering many areas relevant to Japanese Knotweed, our free downloadable How-to Guides, and Product Reviews on the latest methods being employed to eradicate or remove Japanese Knotweed.
Knotweed Removal, UK