Getting rid of Japanese knotweed

mabchapman · Apr 30, 2012

ClaraLou said: ↑
Hi there madchapman

Don't chuck diesel around and don't panic because it won't help!

One of the many problems with knotweed is that any little broken piece of material which you ignore can quickly make a new plant. This means that digging out roots and burning them can be counterproductive, because you will always leave bits of root in the ground which will regenerate. In fact, the plant positively thrives on this sort of disturbance. It's better to leave the plant alone and zap it with weedkiller.

My next-door-but-one neighbour inherited a thriving patch of Japanese knotweed. It started to spread under the fence to my direct neighbour's garden. When she had to go into a care home and the garden became neglected, I had nightmares about the stuff getting into my flowerbeds. So I'm afraid I trespassed a bit and zapped the stuff with weedkiller. I can't remember which one but it was just an ordinary brand - Resolva, I think. I just kept spraying and spraying and spraying;fortunately there was nothing much else in that part of the garden which might have got damaged by it.

Well, two years on and - touch wood - I've yet to see those sinister shoots make a reappearance. I might be being too optimistic; it is incredibly difficult stuff to kill. But I have certainly stopped it in its tracks for a bit.

I remember Pete saying that wild patches that are left alone don't seem to spread as much as you might fear; I think he's right. Disturbing knotweed is the worst thing you can do. Leave the roots alone, don't try to dig them out - instead, use a systemic spray which will get taken down to the roots and hopefully kill them. The other thing is that when professionals tackle knotweed they are extremely careful not to transport bits of it on clothing or shoes, because you can unwittingly spread it around.

Shame we can't eat the stuff. We could cure world hunger at a stroke.

PS I read a magazine article a while back which suggested an interesting method of control. Cut the tops of the shoots off, leaving the hollow stems. Make yourself a d-i-y funnel out of a drinking straw and pour weedkiller into the stem. Cover with a plastic bag secured with wire closure et voila! I haven't tried it but it sounds worth a go.
Click to expand...

ClaraLou said: ↑
Hi there madchapman

Don't chuck diesel around and don't panic because it won't help!

One of the many problems with knotweed is that any little broken piece of material which you ignore can quickly make a new plant. This means that digging out roots and burning them can be counterproductive, because you will always leave bits of root in the ground which will regenerate. In fact, the plant positively thrives on this sort of disturbance. It's better to leave the plant alone and zap it with weedkiller.

My next-door-but-one neighbour inherited a thriving patch of Japanese knotweed. It started to spread under the fence to my direct neighbour's garden. When she had to go into a care home and the garden became neglected, I had nightmares about the stuff getting into my flowerbeds. So I'm afraid I trespassed a bit and zapped the stuff with weedkiller. I can't remember which one but it was just an ordinary brand - Resolva, I think. I just kept spraying and spraying and spraying;fortunately there was nothing much else in that part of the garden which might have got damaged by it.

Well, two years on and - touch wood - I've yet to see those sinister shoots make a reappearance. I might be being too optimistic; it is incredibly difficult stuff to kill. But I have certainly stopped it in its tracks for a bit.

I remember Pete saying that wild patches that are left alone don't seem to spread as much as you might fear; I think he's right. Disturbing knotweed is the worst thing you can do. Leave the roots alone, don't try to dig them out - instead, use a systemic spray which will get taken down to the roots and hopefully kill them. The other thing is that when professionals tackle knotweed they are extremely careful not to transport bits of it on clothing or shoes, because you can unwittingly spread it around.

Shame we can't eat the stuff. We could cure world hunger at a stroke.

PS I read a magazine article a while back which suggested an interesting method of control. Cut the tops of the shoots off, leaving the hollow stems. Make yourself a d-i-y funnel out of a drinking straw and pour weedkiller into the stem. Cover with a plastic bag secured with wire closure et voila! I haven't tried it but it sounds worth a go.
Click to expand...

ClaraLou

Thank you very much for taking the time to answer - I can see the logic in leaving the plant undisturbed etc. etc. and am waiting a few more days so there is nice fresh growth to attack. I will keep you posted - perhaps I wont use the deisel which would only stink the place out, kill the soil and maybe the cats! Thank you once again Mabchapman

Aesculus · Apr 30, 2012

ClaraLou said: ↑
Shame we can't eat the stuff. We could cure world hunger at a stroke.
Click to expand...

I'm pretty sure you can eat the stuff you blanch the tips if I remember rightly

gcc3663 · Apr 30, 2012

Aesculus said: ↑
I'm pretty sure you can eat the stuff you blanch the tips if I remember rightly
Click to expand...

That's the answer Aesculus. Publish the recipe, start a rumour that there's a shortage, and let the publics panic button devour the available supply

Aesculus · Apr 30, 2012

The young stems are edible as a spring vegetable, with a flavor similar to mild rhubarb. In some locations, semi-cultivating Japanese knotweed for food has been used as a means of controlling knotweed populations that invade sensitive wetland areas and drive out the native vegetation
Click to expand...

cutesy of Wikipedia

Jack McHammocklashing · Apr 30, 2012

http://www.bbc.co.uk/iplayer/episode/b01gxvgw/Beechgrove_Garden_2012_Episode_5/

Beechgrove garden 06.48 in Knot Weed

Jack McHammocklashing

Scorpio1968 · May 1, 2012

I had this stuff at my previous house which had spread from the neighbours garden. I recognised it straight away and warned him but he didn't do anything about it. I used Roundup which kept it in check on my side of the fence and i reported my neighbour to the council. I moved eventually so no idea what happened. Bloody Victorians.

ixithepatriot · May 1, 2012

Ive just finished spraying the knotweed in my area i work for local council and we treat it with checking area every 6weeks in the growing season and spraying any growth emerging a few of our sites are on boundaries with private land and they have shoots 3ft - 4ft when on our sites very few shoots and just emerging and some sites no signs we spray roundup 450. stem injection is probably the best way to go but you need to wait until the stems go hollow im sure so have to let them grow a fair height first we have never used it as would be to time consuming on the scale of some of our sites a scythe and a knapsack has worked well for us

Knotweed King · May 13, 2012

are you based in Tingley?

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Getting rid of Japanese knotweed

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gcc3663 Knackered Grandad trying to keep up with a 4yr old

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Knotweed King Apprentice Gardener

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Getting rid of Japanese knotweed

mabchapman Apprentice Gardener

Aesculus Bureaucrat 34 (Admin)

gcc3663 Knackered Grandad trying to keep up with a 4yr old

Aesculus Bureaucrat 34 (Admin)

Jack McHammocklashing Sludgemariner

Scorpio1968 Gardener

ixithepatriot Apprentice Gardener

Knotweed King Apprentice Gardener

Getting rid of ants in block paving

Getting rid of bamboo roots

Getting Rid of Sanfoin

Getting rid of ivy and shrubs in a border

Getting rid of course grass in Lawn

Share This Page

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