Any recommendations for dealing with Japanese Knotweed?

(13 Posts)
ShutYerCakeHole Tue 16-Aug-16 10:29:44

We have a small shoot. Has anyone treated it successfully, and what did you use?

Thanks in advance!

minipie Tue 16-Aug-16 12:06:13

Not myself but I know someone who has. Concentrated glyphosate, applied daily (I think she painted it on the leaves so as not to kill other plants). Worked in the end.

minipie Tue 16-Aug-16 12:07:11

Also, is there any sign of it in neighbours' gardens as obviously they will need to treat too.

concertplayer Tue 16-Aug-16 12:31:19

This should be treated by a professional JKW company. They will charge
c£200 for an appraisal initially. Any treatment will be insurance backed
which you will absolutely need when you sell in the future.
It is a highly invasive plant and if you touch it when it is flowering just one seed can spread it.
A company can check the canes and indicate if it is has been there a long time etc Poor you!
Legally if you cut it you must dispose of it correctly ie not in household
garden waste. When you sell you will have to admit it and if you do not
and the new occupants discover it they can sue you. The problem being
you can never be 100% sure it will not return so indemnity insurance will
normally be max 10 years. A mortgage and buildings insurance will be
declined unless there is a treatment plan .
Any spray treatment will take min 3 years and companies have stronger
chemicals so a good idea I personally think.
Yeswe do have experience of this btw
They can also do a complete excavation but could be costly if digging up
concrete etc
Strongly recommend you first consult RICS as they can indicate the scale
of the situation ie the nearer your OR ANYBOBY ELSES PROPERTY the
worse it is

albertcampionscat Tue 16-Aug-16 15:21:57

Google rhs and knotweed. There's very helpful guidance.

HolaWeenie Tue 16-Aug-16 15:34:23

Unfortunately yes, we have experience. We opted not to self treat and engaged a professional, with have an eradication plan in action now with an insurance backed guarantee. (Should we sell any surveyor would ok it and lendors will lend against it)

Interestingly after paying my specialist, he said that had I gone ahead and self treated (i bought the stuff, it's sitting in the shed) it would be unlikely that I would have killed it off, if you don't kill it off within the first couple of years with the strong stuff the plant just mutates and you end up with bonsai JK, so teeny tiny plants that should be 7ft tall but still with all the potency of the full sized ones.

Also you have a small shoot? You would need it to grow to about 5ft before treating it so that it sends a big dose down to the root.

weegiemum Tue 16-Aug-16 15:51:41

We had it along the side of a river in our garden.

We were in the Scottish islands so far from professionals so dealt with it ourselves. 10 years ago on a still day we weedkillerd the whole lot. Did that again with any sprouts. Then carefully checked and trimmed off any further shoots. Been JKW free now for 9 years. We still check regularly as a neighbour has a patch he won't treat. The bit we treated is now lovely with primroses and daffodils that had been suppressed.

concertplayer Tue 16-Aug-16 15:58:19

Hola, did I get it right? Are you saying it is better to let it grow to 5ft
as you will get a better result with treatment at that height?

JT05 Tue 16-Aug-16 16:22:21

With just one small shoot how do you know it's JKW. Is there some more nearby? Some plants send up similar shoots.

minipie Tue 16-Aug-16 16:36:12

The person I know who self treated theirs successfully (still lives there 20+ yrs later and no reappearance) definitely treated it when still a couple of small shoots and didn't let it grow to 5ft!

Doing it professionally and with a guarantee is a better bet if you plan to sell or remortgage soon however.

HolaWeenie Tue 16-Aug-16 16:41:22

Yup, called my guy in when I saw shoots, he confirmed, we let it grow to 4/5ft and he injected every plant that had grown. I could have told him to inject shoots, but I listened to his advice and it made sense to me the stronger the plant the more it's sending back to the root, so far so good, all looking very dead. In fact the best time to treat is September when the plant is dying back to the root for winter, but I didn't have the nerve to wait, and he agreed as its on the side of our house.

I wanted the security of the insurance backed guarantee for property resale purposes, we don't plan on going anywhere but you never know what life has in store. With that policy we shouldn't see a depreciation in value of any problems with lending.

ShutYerCakeHole Tue 16-Aug-16 19:47:40

Thanks so much for all replies.

weegie we're in a similar situation, do you remember what products you used?

JT05 it's rampant on a neighbour's land (he's trying to ignore it, but we have reported him) so we know it has now spread to us, it is identical.

No plans to sell or remortgage, but we wouldn't want to spread it anywhere else!

Thanks again will look into all advice above.
If anyone can recommend products I'm all ears!

ancientoak Thu 18-Aug-16 12:22:24

Hi & sorry if this is a repeat message - I thought I'd posted several hours ago but nothing has appeared !
We are dealing successfully with JK on a patch of unregistered land some way behind our house.
Steps taken so far :
Bought a sprayer from garden centre - £12.99
Bought weed killer from garden centre - £7.99 to £9.99 (Bayer Garden Super Strength Glysphosate 680g/kg strength)
Bought incinerator bin from Aldi - £12.99

We sprayed twice last year with great success. This years re-growth has been minor. We have sprayed once this year but are prepared for this to be a longer term project.
Best advice shouted loudly - TRUST THE RHS SITE. JK does NOT seed in the UK. You CAN use the injection method yourself if you fancy the fiddling around ( equipment from ebay ) You do NOT need a so called free survey which will lead to a massive quote - unless you need to sell your house instantly.
You CAN dispose of the debris yourself easily as follows.
Put the incinerator next to the dead stalks on Nov 3rd
Cut the stalks on Nov 4th
Burn them on Nov 5th
Last method solves all the removal problems / bonfire smoke probs.
Hope this helps

ps a lot of the Local Authority sites say main problems with spread are caused by traffic etc. to/from building sites. Interesting that removal companies we contacted last year wanted to use heavy digging equipment !!

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