People are always on the lookout for inventive ways to deal with Japanese knotweed. In a previous blog, we looked at whether salt could dehydrate and eventually kill it off, but sadly, the answer was no. Professional herbicides were required to deal with this hardy invasive species! But can any other naturally occurring materials kill Japanese knotweed?
Today we're looking at a different substance to see whether or not it can do a better job. As you can see from the title, today we're looking at the weed-killing properties of lime. No, not the kind that's often sliced and served in a mojito, the kind that's found in the earth's crust as limestone, chalk and marble.
Lime, also known as calcium carbonate, has been used for centuries to neutralise acidic soils, and in very small doses, it has antacid properties which can help relieve indigestion. It's incredibly alkaline with a pH of 9.91 and in large quantities, it's harmful to humans, animals and ultimately plants too. But can it kill Japanese knotweed?
One of the main problems with Japanese knotweed is that it's very good at surviving in challenging soil conditions and has been known to grow in both alkaline and acidic soils. So, adding lime to the soil might seem like a no-brainer solution to your Japanese knotweed problem, but in reality, it might not make much difference at all.
If you do decide to add lime to the soil around your Japanese knotweed infestation, there's a small possibility that you'll burn the stem, however, you won't effectively kill the root system that exists underground. If anything, you're putting surrounding plants and pets at risk, so please don't go spreading lime all over your garden.
See Also: Can Bleach Kill Japanese knotweed?
What should I do if I have a Japanese knotweed infestation?
In our experience, there are very few (if any) DIY remedies that will eradicate Japanese knotweed completely. Our advice? If you find Japanese knotweed on your property, you should get it checked out and treated by professionals as soon as possible!
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Some things are best left to the professionals. If you have any questions about treating Japanese knotweed, please feel free to get in touch.