@pippip Well done you! I'll consider myself to be a knotweed graduate once we go the next year without any visible regrowth.
I have bindweed too and tackled that with glyphosate when we did the knotweed (based on excellent advice from this forum - bundle into a ziplock bag, spritz and leave to bake for a while).
Here's what I did with the knotweed (from upthread):
Let it grow and treat with Glyphosate from July/August onwards (cut down and fill the hollow stems, making sure to do this in a period of dry weather). For the smaller stems - which will not be hollow - apply on both sides of the foliage. Repeat the treatment after a month for any parts that still look healthy (for our second application, instead of the timeconsuming foliar wiping method, we experimented with mixing up a glyphosate foam and applied it to the leaf nodes). (I also pruned the knotweed down in June to manage the height but I wouldn't advise this as it just formed a more branchy thicket). Our infestation was about 1x8m down one side of the garden, and in isolated bunches elsewhere. Some canes were as thick as my thumb, others only a chopstick. To add to the joy, lots of midges or some other biting fly had moved in.
We did this last year and all the stands we treated have not returned, but we had some isolated growth emerge this year in new spots. I'm not sure if these are just fragments that were dormant or other parts of the root system being activated, but we'll repeat the treatment and then improve the soil (because it's a new build) and plant. I've read that digging could also reactivate any dormant sections, but we'll just have to deal with that if it happens, as I'm not willing to wait another year to have a garden! (:
@Molamola Well, that’s pretty much the technique I
used! Particularly
cutting down towards the end of the growing season and filling the hollow stems. I also sprayed early season when in full leaf,
but not double-sided. I know you can
also bruise / scrunch the leaves lightly then spray them.
By the way, this was almost 20 years ago.
It was in various areas. One being at the
end of the garden in a raised bed which was full of it - an area about 2ft high x 30ft wide
x 10ft deep [60cm high x 9m wide x 3m deep]. I treated the area as above,
then decided I wanted to dismantle the raised bed and completely level it.
I probably treated the knotweed again as
above, but eventually I went through the bed removing the knotweed and as much
of the root as possible by hand, then I spread the soil by the wheelbarrow to a nearby
part of the end garden. I went through it a spade load at a time filling
the wheel barrow picking out even the tiniest bits of root then I’d spread and tip
out the soil to it’s new location. I
realised while I was digging up the raised bed soil area I was exposing the
roots which were then drying out and would die - same with the barrow loads of
soil I was thinly spreading around was exposing and drying out any roots I missed. It’s pretty well never re-grown, perhaps 3
or 4 shoots in that area.
My neighbour still has a big patch of it at
the end of his garden - I used to spray it but stopped when I’d dealt with mine.
His has never really spread.
___________________________________
However, big tip: I used “Root
Out” i.e. ammonium sulphamate, I found it much more effective than glyphosate. It's used to control tough
woody weeds, tree stumps, brambles, ivy, marestail/horsetail, etc and I believe,
honey fungus.
However, in 2008 the EU removed its
approval as a registered herbicide so it can’t be advertised or sold explicitly
for this purpose. It’s still sold but as a ‘compost accelerator’ - thus
unaffected by the EU’s pesticide legislation.
It gradually degrades to sulphate of ammonia, a nitrogen fertiliser
I’ve actually just bought some again after
all these years.
I also recently read that Japanese Knotweed
is edible. So I ate some!
I was in a hurry so I just fried some
quickly. A few stems turned to the texture of straw, a bit woody, but otherwise
it was quite nice, lemony. Next time I will
par-boil it before hand, or perhaps have it raw...
Posts
I have bindweed too and tackled that with glyphosate when we did the knotweed (based on excellent advice from this forum - bundle into a ziplock bag, spritz and leave to bake for a while).
Here's what I did with the knotweed (from upthread):
Let it grow and treat with Glyphosate from July/August onwards (cut down and fill the hollow stems, making sure to do this in a period of dry weather). For the smaller stems - which will not be hollow - apply on both sides of the foliage. Repeat the treatment after a month for any parts that still look healthy (for our second application, instead of the timeconsuming foliar wiping method, we experimented with mixing up a glyphosate foam and applied it to the leaf nodes). (I also pruned the knotweed down in June to manage the height but I wouldn't advise this as it just formed a more branchy thicket). Our infestation was about 1x8m down one side of the garden, and in isolated bunches elsewhere. Some canes were as thick as my thumb, others only a chopstick. To add to the joy, lots of midges or some other biting fly had moved in.
We did this last year and all the stands we treated have not returned, but we had some isolated growth emerge this year in new spots. I'm not sure if these are just fragments that were dormant or other parts of the root system being activated, but we'll repeat the treatment and then improve the soil (because it's a new build) and plant. I've read that digging could also reactivate any dormant sections, but we'll just have to deal with that if it happens, as I'm not willing to wait another year to have a garden! (:
@Molamola Well, that’s pretty much the technique I used! Particularly cutting down towards the end of the growing season and filling the hollow stems. I also sprayed early season when in full leaf, but not double-sided. I know you can also bruise / scrunch the leaves lightly then spray them.
By the way, this was almost 20 years ago.
It was in various areas. One being at the end of the garden in a raised bed which was full of it - an area about 2ft high x 30ft wide x 10ft deep [60cm high x 9m wide x 3m deep]. I treated the area as above, then decided I wanted to dismantle the raised bed and completely level it.
I probably treated the knotweed again as above, but eventually I went through the bed removing the knotweed and as much of the root as possible by hand, then I spread the soil by the wheelbarrow to a nearby part of the end garden. I went through it a spade load at a time filling the wheel barrow picking out even the tiniest bits of root then I’d spread and tip out the soil to it’s new location. I realised while I was digging up the raised bed soil area I was exposing the roots which were then drying out and would die - same with the barrow loads of soil I was thinly spreading around was exposing and drying out any roots I missed. It’s pretty well never re-grown, perhaps 3 or 4 shoots in that area.
My neighbour still has a big patch of it at the end of his garden - I used to spray it but stopped when I’d dealt with mine. His has never really spread.
___________________________________
However, big tip: I used “Root Out” i.e. ammonium sulphamate, I found it much more effective than glyphosate. It's used to control tough woody weeds, tree stumps, brambles, ivy, marestail/horsetail, etc and I believe, honey fungus.
However, in 2008 the EU removed its approval as a registered herbicide so it can’t be advertised or sold explicitly for this purpose. It’s still sold but as a ‘compost accelerator’ - thus unaffected by the EU’s pesticide legislation. It gradually degrades to sulphate of ammonia, a nitrogen fertiliser
I’ve actually just bought some again after all these years.
I also recently read that Japanese Knotweed is edible. So I ate some!
I was in a hurry so I just fried some quickly. A few stems turned to the texture of straw, a bit woody, but otherwise it was quite nice, lemony. Next time I will par-boil it before hand, or perhaps have it raw...