Your browser isn't supported
It looks like you're using an old web browser. To get the most out of the site and to ensure guides display correctly, we suggest upgrading your browser now. Download the latest:

Welcome to the MSE Forums

We're home to a fantastic community of MoneySavers but anyone can post. Please exercise caution & report spam, illegal, offensive or libellous posts/messages: click "report" or email forumteam@.

Search
  • FIRST POST
    • SandraScarlett
    • By SandraScarlett 24th May 19, 5:42 PM
    • 3,957Posts
    • 28,811Thanks
    SandraScarlett
    Japanese Knotweed - one shoot!
    • #1
    • 24th May 19, 5:42 PM
    Japanese Knotweed - one shoot! 24th May 19 at 5:42 PM
    My neighbour was watering my garden whilst I was away and has told me he has discovered Japanese Knotweed at the bottom. I had no idea what it looked like.

    I've phoned several companies and have had eye watering quotes, just to carry out a survey, and just one has said it was free and they are coming next week.

    Once I looked at the area closely, I could see there is just one shoot and I wondered if there is any way I could treat this myself.

    Any advice would be gratefully received.
Page 1
    • donmaico
    • By donmaico 24th May 19, 7:16 PM
    • 336 Posts
    • 50 Thanks
    donmaico
    • #2
    • 24th May 19, 7:16 PM
    • #2
    • 24th May 19, 7:16 PM
    My neighbour was watering my garden whilst I was away and has told me he has discovered Japanese Knotweed at the bottom. I had no idea what it looked like.

    I've phoned several companies and have had eye watering quotes, just to carry out a survey, and just one has said it was free and they are coming next week.

    Once I looked at the area closely, I could see there is just one shoot and I wondered if there is any way I could treat this myself.

    Any advice would be gratefully received.
    Originally posted by SandraScarlett
    you could try using a Glyphosate-based weedkiller such as Roundup Tree Stump & Rootkiller. Spray the leaves and canes well and keep an eye of it as you will need to do further reprays .It can take 3 years to get rid of the stuff so prepare for regrowth next spring when it will look somewhat different
    Argentine by birth,English by nature
    • Grenage
    • By Grenage 24th May 19, 7:31 PM
    • 1,766 Posts
    • 1,653 Thanks
    Grenage
    • #3
    • 24th May 19, 7:31 PM
    • #3
    • 24th May 19, 7:31 PM
    Are you sure it's knotweed? I'd also use a Glyphosate solution; might be worth reading up on the best time to apply.
    • daveyjp
    • By daveyjp 24th May 19, 7:35 PM
    • 8,072 Posts
    • 6,665 Thanks
    daveyjp
    • #4
    • 24th May 19, 7:35 PM
    • #4
    • 24th May 19, 7:35 PM
    First confirm it is knotweed. If it is one shoot there will be far bigger shoots nearby.

    Take some photos, upload and share the link here.

    Anyone who says they are a 'specialist' will probably rip you off so be careful. From experience. "specialist" quote, £12,000, local grounds maintenance company £500.

    If it is knotweed don't do anything for 2-3 months.
    • Davesnave
    • By Davesnave 24th May 19, 11:40 PM
    • 28,415 Posts
    • 100,135 Thanks
    Davesnave
    • #5
    • 24th May 19, 11:40 PM
    • #5
    • 24th May 19, 11:40 PM
    Look around at neighbours to see if it may have originated there, and get a positive ID , because there are plants that look like knotweed, and aren't. If a neighbour has it, it's important to get them on board.

    You have plenty of time to read-up on treatment if it is. There are no magic formulas and you can do this yourself with such a small amount.

    As davey suggests, don't be panicked into signing-up to an expensive treatment programme and expect any 'free' survey to be as pleasant as the average double-glazing sales pitch!
    'I've suffered for my music, now it's your turn.' Neil Innes, introducing 'Protest Song.'
    • SandraScarlett
    • By SandraScarlett 25th May 19, 2:41 PM
    • 3,957 Posts
    • 28,811 Thanks
    SandraScarlett
    • #6
    • 25th May 19, 2:41 PM
    • #6
    • 25th May 19, 2:41 PM
    Thank you for all the helpful replies. Alas, I'm not able to upload photos, but the neighbours have confirmed it is knotweed, though they, as yet, don't have any.


    A friend has told me he treated his in June and September, with a product he bought some years ago, which is apparently a type of "Commercial Strength Glyphosate", and isn't available now.


    He had a few stems, as opposed to my solitary one, and treated his by digging down about one foot, burning the stems, inserting a metal cylinder (he suggested a baked beans can, washed thoroughly and both ends removed) and pouring this stuff down, then covering the hole with a large paving stone.


    He then did this for about 3 years, after which nothing else appeared. Other people present during this conversation, all nodded in agreement, and some mentioned other products that they still had in their sheds, that you cannot buy now.


    What do you folk think?
    • DaftyDuck
    • By DaftyDuck 25th May 19, 3:50 PM
    • 4,439 Posts
    • 9,444 Thanks
    DaftyDuck
    • #7
    • 25th May 19, 3:50 PM
    • #7
    • 25th May 19, 3:50 PM
    No, not the correct technique. Keen gardener, hobby farmer with (ex)knotweed problem, and sometime Bayer SME scientist ( now owners of Monsanto). Mind you, I have a different area of expertise...

    Glyphosate is pretty well instantly inactivated by contact with soil. Spectacularly so. Smother a pair of plants with glyphosate, then chuck a couple of handfuls of soil on one, and only one dies. With your friend's technique, the glyphosate is not taken up by the growing part of the plant, and is pretty much inactivated instantly anyway. Tin? Stone on top? Ha, he's just hiding his folly from others!

    Correct technique is to wait until growth is maximal, usually after August. Either spray twice three days apart at normal dilutions, or inject directly into hollow stem, at 1.5X concentration.

    Given you have but one stem, I might be tempted to carefully dig it up, but we are talking Time Team style, slowly with a hand trowel at most. You need to follow all the root back. You will still need to glyphosate before doing this, and wait a month plus after that before excavation, but it might help.

    If it is away from your property, and not coming in from the neighbours, I would try treating it yourself.
    • Davesnave
    • By Davesnave 25th May 19, 5:16 PM
    • 28,415 Posts
    • 100,135 Thanks
    Davesnave
    • #8
    • 25th May 19, 5:16 PM
    • #8
    • 25th May 19, 5:16 PM


    He then did this for about 3 years, after which nothing else appeared. Other people present during this conversation, all nodded in agreement, and some mentioned other products that they still had in their sheds, that you cannot buy now.


    What do you folk think?
    Originally posted by SandraScarlett
    There is no 'commercial strength glyphosate' one cannot buy now. I've recently become licensed to buy the strongest type, but I've been buying it over the internet for years without any questions being asked! The 360g/litre stuff is fine anyway.

    Dafty is also right about technique.

    The weedkiller many of us shouldn't have in our sheds is probably Sodium Chlorate, which was withdrawn in 2011. I'm not sure that would be any more effective though.
    'I've suffered for my music, now it's your turn.' Neil Innes, introducing 'Protest Song.'
    • SandraScarlett
    • By SandraScarlett 25th May 19, 9:30 PM
    • 3,957 Posts
    • 28,811 Thanks
    SandraScarlett
    • #9
    • 25th May 19, 9:30 PM
    • #9
    • 25th May 19, 9:30 PM
    Given you have but one stem, I might be tempted to carefully dig it up, but we are talking Time Team style, slowly with a hand trowel at most. You need to follow all the root back.


    Do you mean I should dig all around the stem with a hand trowel?


    You will still need to glyphosate before doing this, and wait a month plus after that before excavation, but it might help.

    If it is away from your property, and not coming in from the neighbours, I would try treating it yourself.


    It's very near the fence, and the adjacent new neighbour, who is not the friendliest, has only recently started digging over his garden. I asked if he'd come across this knotweed, he lifted the fence panel to look at my solitary shoot, and denied he'd dug up anything like that. But he would say that, wouldn't he!
    • DaftyDuck
    • By DaftyDuck 26th May 19, 6:38 AM
    • 4,439 Posts
    • 9,444 Thanks
    DaftyDuck
    The stem will have a long yellowish-centred fibrous root that may travel horizontally several feet. Even a fingernail size fragment will have the potential to grow. You must use glyphosate first. Then gently dig out all the root a month later, when it has been mostly killed.

    And your neighbour - who appears to have just dug over his garden - would say that, wouldn't he! That doesn't mean you're did come from him, but it does mean you need to stop it spreading to him....
    • SandraScarlett
    • By SandraScarlett 27th May 19, 2:07 PM
    • 3,957 Posts
    • 28,811 Thanks
    SandraScarlett
    Thank you for all your replies. I've emailed the person coming this week to confirm I don't have to pay for the visit (want something in writing), and as the company's cost is likely to be mega expensive, I'll try the DIY method.

    Can I just confirm that I should wait till August to treat this?

    And then I should spray everything with glyphosate?

    After which I should wait a few days, and then spray again.

    Then wait a few weeks, and then try digging it up with a hand trowel.

    I must have some very sick slugs nearby, as a lot of the leaves appear to have been partially eaten!
    Last edited by SandraScarlett; 14-06-2019 at 5:22 PM.
    • DaftyDuck
    • By DaftyDuck 30th May 19, 8:23 PM
    • 4,439 Posts
    • 9,444 Thanks
    DaftyDuck
    Not sick slugs, choosy ones! It's very tasty, like asparagus apparently. Haven't tried it, but supposedly so.

    Yes, that's the right technique. But....

    ... I probably shouldn't advise this, but.... Is it really only one stem, and do you think it arrived on sole of shoe/brought in somehow, rather than spreading from neighbour? If so, I might personally be tempted to treat it now, and repeat treatment on any bit that comes up for a month, then excavate. That's just a personal opinion, and I'm a very thorough digger-upper!
    • theoretica
    • By theoretica 31st May 19, 10:16 PM
    • 5,848 Posts
    • 7,245 Thanks
    theoretica
    Several of the companies will confirm from photographs if something is knotweed, for free. Depends on if you trust and believe your neighbours or want further confirmation.
    But a banker, engaged at enormous expense,
    Had the whole of their cash in his care.
    Lewis Carroll
    • Apodemus
    • By Apodemus 1st Jun 19, 10:27 AM
    • 1,353 Posts
    • 1,120 Thanks
    Apodemus
    Lots of good advice above. With all due respect to your neighbour, you really need to get a proper second opinion to verify that it is indeed knotweed. One stem of knotweed is like “one ant”, yes they occur but it is relatively rare to see one isolated from its source.

    Personally, I wouldn’t wait till August, but would nuke it with glyphosate now and repeat for as long as necessary. Every day you leave it, the roots are getting longer and the risk that the glyphosate doesn’t completely kill it increases.

    Also, if you decide to dig it up, you need to think through what you are going to do with the material - it must not go to compost or general landfill, as it is scheduled waste and needs to be handled properly. Digging runs the risk of breaking up live roots and increasing the number of plantlets next year, so I would leave it where it is and keep on top of the weed killing.
    • Car1980
    • By Car1980 2nd Jun 19, 1:50 PM
    • 272 Posts
    • 138 Thanks
    Car1980
    Relax. Get some Roundup Provantage and spray it this month.

    https://www.pitchcare.com/shop/professional-total-weed-killers/roundup-provantage.html

    The leaves will go yellow and drop off after about 10-14 days. You'll think it's not
    working, whereas it'll be circulating through the plant, which is what you want. Only spray once and don't dig it up.

    If it's one shoot it is unlikely to appear again next year. But if it does, spray again in June (no earlier).

    Then just avoid digging around the location of the shoot.

    Knotweed is killable - you just have to use the right weed killer and spray every June like clockwork. A massive stand will be gone in 4 or 5 years this way (although it's recommended to stem inject big stands in September in addition to spraying).
    Last edited by Car1980; 02-06-2019 at 1:52 PM.
    • SandraScarlett
    • By SandraScarlett 14th Jun 19, 5:20 PM
    • 3,957 Posts
    • 28,811 Thanks
    SandraScarlett
    Well the expert came, confirmed it JKW, at which point, I cried. He hugged me and said "There, there. I shouldn't say this, but …………………..".


    He said as it was only one stem, there was no way he could charge me the thousands of £s it would cost, and to treat it with a product that he got me, that cost me £4.75!!


    I sprayed it every other day, as per his instructions, and it's already died back, with just a stem showing. Apparently, I should attempt to dig that up, if I can, or if not, cut it right back and either burn the stem, or dispose of it in the black bin bag collection.


    If it appears again next year, I should repeat the process. Apparently, it can be wind-borne, be brought in by a fox, or even a mouse, or it could have come from next door, who have laid paving stones over the area they dug up.


    But at least now I know, and thank you all so much for your wonderful help.
    • Davesnave
    • By Davesnave 14th Jun 19, 6:46 PM
    • 28,415 Posts
    • 100,135 Thanks
    Davesnave
    Good! Dafty's post 12 said much the same.

    Just keep a weather eye out.
    'I've suffered for my music, now it's your turn.' Neil Innes, introducing 'Protest Song.'
    • DaftyDuck
    • By DaftyDuck 14th Jun 19, 8:28 PM
    • 4,439 Posts
    • 9,444 Thanks
    DaftyDuck
    ... and Dafty agrees with himself. His JK has failed to appear this year, but e is keeping his beak peeled!
    • greyteam1959
    • By greyteam1959 15th Jun 19, 3:41 PM
    • 2,642 Posts
    • 1,243 Thanks
    greyteam1959
    And what was this magic £4.75 product that the guy produced ??
    Brand name or active ingredient please.
Welcome to our new Forum!

Our aim is to save you money quickly and easily. We hope you like it!

Forum Team Contact us

Live Stats

811Posts Today

6,496Users online

Martin's Twitter
  • Channel 4 really screwed up not doing this on the Tory leaders debate last night, just think of the ratings... https://t.co/eYYfAYGdck

  • Teacher/head in a London(ish) senior school? I want film a 1hr ish talk to 16-18 yr olds on student finance (to put? https://t.co/dSsSp1UVDF

  • RT @thismorning: As a ban on rip-off bank fees is announced, @MartinSLewis explains if you can reclaim, and how to cut your overdraft costs?

  • Follow Martin