Killing Japanese Knotweed with Bleach – Does it Work?
Japanese knotweed is a highly invasive, non-native species and can cause chaos in gardens, as well there’s the potential to be acquitted for criminal damage if it’s left untreated.
However, due to the disruption and damage that Japanese knotweed can cause, some people turn to DIY methods for the eradication of knotweed with household chemicals, such as bleach. This is an ineffective approach to treating Japanese knotweed, and it will cause more damage to wildlife than good.
Will Bleach Kill Japanese Knotweed?
No, bleach will not kill Japanese knotweed. Instead, it will end up causing even more damage to your garden, where it’s harmful to the soil, and will not affect Japanese knotweed at all.
Why Does Bleach Not Kill Japanese Knotweed?
While bleach is a highly effective household detergent and disinfectant, it will only kill germs and bacteria, not highly invasive species of weed. Bleach is a dilute solution made of sodium hypochlorite, which decomposes to create chlorine.
Bleach will only kill bacteria to create a disinfected surface. It will not, however, kill a plant made of natural materials, as it is not a bacterium.
Why You Shouldn’t Use Bleach to Kill Knotweed
Aside from its ineffectiveness, there’s numerous reasons as to why you shouldn’t use bleach to try and kill knotweed.
1. The Negative Impact on the Environment
Bleach is not a good chemical for the environment, whether in the manufacturing process or as a cleaning product in its daily use. If mixed with the wrong chemicals or left open, it can release harmful gases into the atmosphere, which contribute to the reduction in health of the ozone layer.
2. The Damage to Other Plants
Bleach – specifically chlorine bleach – will not only wither away any nearby plants, but will also contaminate your soil, as it will have a pH that is too high and too salty for plants to inhabit. As bleach kills organic matter, it also diminishes the presence of bacteria and fungi that are essential to plant growth.
In short, bleach is not an effective treatment for Japanese knotweed. It will actually harm your garden, creating an unsafe and hostile environment for future plant growth.
3. It Will Create More Root Growth
As Japanese knotweed is spread through the root system rather than the leaves or pollination, treating Japanese knotweed with bleach will only damage the insignificant part of the plant. Reacting to this damage, what may actually happen is that the roots begin to spread even further, looking for a safer place to sprout.
How to Safely Eradicate Japanese Knotweed
Japanese knotweed can only be completely eradicated by removal. While glyphosate-based herbicides such as RoundUp can successfully remove knotweed, it cannot guarantee the complete effectiveness of the removal.
There are numerous ways that you can actually kill Japanese knotweed. One of the more popular long-term solutions is regular stem injection with an industrial based glyphosate herbicide. This not only protects other plants around the area but ensures that the herbicide is delivered straight to the roots.
The most effective method for removal is excavation mixed with another treatment, such as herbicides or burial if the site is big enough.
If you’re looking for a guaranteed method to remove Japanese knotweed, backed by industry accredited schemes, then speak to the experts at Japanese Knotweed Specialists. We’re able to create a Japanese knotweed management plan and work considerately within your garden or green space to remove Japanese knotweed effectively.