The dreaded Japanese knotweed

[Livingintheclouds]

After losing two houses due to seller being ill and withdrawing and another not funding an onward purchase and me withdrawing (and seller now taking house of the market), both after spending thousands on getting searches and surveys, I'm getting desperate. I'm moving some distance for school, have already completed on my sale and am in a holiday let costing me £££ (it was only to be for the two or three weeks before purchase).
Tomorrow we go see a house just come back to the market. It's near the last house, so I know the area and it's a grid of Victorian terraces so they are all pretty much same layout.
The EA says there was a small amount of Japanese knotweed found by previous survey (this is not the main reason the buyers pulled out). The seller immediately got it assessed and has started a treatment which comes with a transferable 10 year guarantee. I understand this is acceptable to most mortgage companies which doesn't concern me as I'm a cash buyer, but of course I will sell it at some point.
I know more recent research has said JK is not as damaging nor as invasive as previously thought, but it's reputation is such that I'm sure many would walk away just in hearing it mentioned. What are your thoughts? It doesn't bother me, but I'm just thinking down the line, probably I another five years or so, when I want to sell.

I have heard that so long as you keep cutting it right down like grass ( and burning it) it cannot photo synthesise and will get weaker and weaker.

Why not ask the advice of a horticultural expert?

Has the price of the house been reduced at all?

It’s the 3m that’s an issue. If it’s more than 7m a way it usually doesn’t affect the mortgage, but many lenders will have an issue if closer than 7m. I think it’s pretty treatable, but your photo shows it right on the edge of a patio - so are there rhizomes below the patio? Was the patio built on it? It is a very strong plant so could pop up through the patio over time as the pointing ages.

You might be ok. You may also not be able to sell the house in future because of the mortgage issue.

If you have a professional treatment plan in place (which it does) then the 3m doesn’t matter.

The plan treats it and also insures you (or at least it should!)

You have to spray the weedkiller down those tubes. The plant then sucks that right down to its roots and that fucks it up good and proper

You can do this, or you can just spray the leaves like you would when using weedkiller on any other plant. I’m a professional horticulturalist and our standard way of treating it is to reduce the stems to six inches in height then spray the leaves, covering them entirely, once a week for six weeks. It doesn’t actually take six weeks though - three treatments usually does the trick. Sometimes it comes back the following year, but it is weaker and one quick spray then sees it off. In my experience.

It really isn’t a big deal.

It is already under a treatment plan that comes with a ten year guarantee. I'm not treating it, the professionals are ( it's not even my house). I have read the updated RICS document which superseds the 2012 one which seems to be where the mortgage companies get the 7m thing - the updated one states it is more 2.5m and overall no more damaging than other woody weeds. But it takes a while for the industry (and public perception) to catch up.
For those who have successfully treated it themselves; did you declare there was JK on the property when you sold? Obviously this property will have it on record plus the neighbours garden has been treated too. I'm wondering if after some years of no reappearance it can be deemed as gone.
It is rampant and I bet way more people have it than realise.

@VenusClapTrap that's interesting what you are saying about the railway line. We've put an offer in on a house with what I thought might be Japanese Knotweed in the back garden but I'm no gardener so I wasn't sure. Have asked the surveyor to look at it (am yet to hear back from him). It backs onto a railway line and I'm now wondering if that's one of the reasons it's there. If it is, it's taking over about 3m of the back garden (though that's still around 15-20m from the house)!

Is it possible to kill it off now? I guess if it's coming from the railway bank, the issue is that unless they kill it off it keeps coming back.

Is that in the back garden @Livingintheclouds?

That's an odd place for a plant to grow. How new is that patio? I would be suspicious how much knotweed is hidden under the patio...

@RumblingTumTumTum if it is JK and it’s throughout the rear 3m of the garden, it’s pretty much guaranteed to be on the other side of the fence along the railway line too. You’d never get rid. Do you have a photo of it?

@RumblingTumTumTum we back onto a railway embankment and there is/was a small JK patch on the railway side of our garden wall. Freaked out as we were remortgaging (the bank's surveyor spotted it!) and got on to Network Rail ASAP. They treated it that week and gave us a letter for the mortgage company 4 days later.

Network Rail have lost a few cases brought by homeowners with JK on their properties from NR land in the last couple of years which may be why they acted so speedily for us!

We got the remortgage

For those who have successfully treated it themselves; did you declare there was JK on the property when you sold?

In my own garden, no. It was one isolated plant that was easily killed and never came back - we moved several years after I dealt with it so pretty confident it was gone for good.

Where I dealt with it professionally for other people, I’ve no idea if they declared it or not. One place was a historic garden that would never come up for sale, so not an issue.

Zinnia - how interesting! Good to hear that Network Rail are taking it so seriously these days. That certainly didn’t used to be the case.

@tilder as I've said it's not my house, but the patio looks several years old.
The house has been tenanted, but I believe the guy who maintains the garden spotted it, so presumably the first occurrence as he would have reported if it had occurred before.

@VenusClapTrap It's possible it had already been treated by the time I called it in - in any event it's looking encouragingly dead now, about a month on. I also phoned NR every day and laid it on quite thick

Don’t believe what the EA says, we have just pulled out of buying a property due to an absolutely shocking survey. I bet they aren’t telling the new buyers, the reason we pulled out, and hoping they won’t have such a through survey. Remember they only get paid if a sale goes through.

I've had an offer accepted. My solicitor will review the guarantee. I've read the most recent government consultation on it and they are asking that the law society consider a time limit if some years have passed since treating without reoccurrence, and that mortgage companies revise their position considering new evidence (the 7m rule is fairly arbitrary and not based on fact). Also it is accepted that it is not as damaging as other shrubs, like buddlea, but it is harder to kill. No other country has the same 'run in the opposite direction' reaction to it. The previous buyers are still living abroad (I know as I'm trying to buy their searches and survey), so the knotweed was not their sole reason for pulling out, and the EA was up front and told me about it before I viewed.

I am buying a house with knotweed and agree with a lot of what you say but in this case I’d be concerned that you might have quite an extensive root network very close to your house with the plant only emerging where it is because of constraints from the patio if you know what I mean? If your house is actually damaged in any way by knotweed I think that will alarm any future buyers even if the treatment is successful in this instance.

I was able to speak to the company that put the treatment plan in place too and suggest you do the same. The owner had to give them permission to speak to me. I would ask them what the best treatment would be in your case rather than what the bare minimum a mortgage provider needs if you know what I mean? Good luck with it!

Thanks @IndecisiveBuyer2021. I sure will be reading the fine print on the knotweed survey and treatment plan, plus my lawyer will ensure it is 'worth the paper it's written on'.
I may well take up part of the patio but as the roots go deep too not sure the benefit. The treatment involves killing off the roots via the stem. The size of infestation counts and it's minimal in this case, with nothing next door. It only goes where there is a weakness and unlikely to be under the house which predates when knotweed was introduced to this country, but obviously the patio is much newer than that.
My friend from another country just looked at me like I was nuts when I mentioned it, in much the same way she did when I asked about cheese and other food restrictions when pregnant! It's just another annoying weed there.

@Livingintheclouds I sent you a PM.
Did you buy the house with JK in the garden?
We’ve just found out there is JK in the garden of the house we are trying to buy.
The lawyer didn’t include the page which referred to it in the sellers information pack, so it’s only just come to light 3 months down the line, following all surveys, searches, mortgage offer etc.
We are so pissed off as they were obviously trying to hide it. The EA says he didn’t know.
We aren’t sure how to proceed yet, don’t have enough information, we also aren’t currently in the UK so can’t go and see the house.
I’ve lost all confidence in our sellers now.

my 92 year old retired gardner cant understand the hysteria and money being made from this weed....expensive treatment plans etc...consultants etc...he used to apply diesel to it...dead in a few days...!!

Sorry name change and yes I did buy it. My sellers did not try to hide it - it was one of the first things the EA mentioned when I rang to view. It had been treated once and is due another soon. Then repeated for the next two to three years with a ten year guarantee. I spoke to the JK guy and he said he thought it was not an issue and that he himself had bought a horse with it. In my case it is two small sprigs, not a major infestation. Buddlea is more damaging but easier to kill, and I can see it right up against houses and even growing out if gutters and no one gives it a second thought.
I received the jk survey and treatment plan and the guarantee and insurance documents. I think I did get the house about 5% below market value too - I think the owners, who live abroad, just wanted it off their hands.
Get them to have it surveyed and get a treatment plan in place - it will be less that £1500 friending in the amount. Has your mortgage company said they will still lend?

Bought a house even!
@earsup it's a requirement by law to disclose it, but I agree there is a hysteria around it which is unwarranted, much like asbestos a couple decades ago and lead paint in the 70s. Obviously these things need to be taken care of properly, but it wouldn't put me off buying.

I'm renting a house with JK in the front garden. The landlord is a friend and simply cannot sell it except at a significant loss (I'm talking about offers close to 20% cash buyer). Be careful!

@maofteens thank you for the update. We still don’t know what to think, obviously one of our issues is the sellers being deceptive so we are feeling unsure about the whole thing.
The house is nice and a good size (in north london) but is already a compromise as it’s on a busy road, the sellers are divorcing and the house is looking unloved, but was originally refurbished about 8/10 years ago just before they bought it.
The husband is living there and he has not been very forthcoming about things, we’ve been pushing for gas/electric certs for about 6 week and they won’t do them, we now know it’s due to electrics needing work.
I don’t know if the mortgage will lend, as we applied without knowledge about JK, I suppose we need to find out what levels it’s at from a JK survey, before we ask them, if the mortgage says no then we will have to pull out anyway as although we are only getting a small mortgage we can’t afford to buy it outright.
We had an offer accepted at 2% under asking which we thought was ok due to the road but now with the electrics (our survey suggested 10k non essential work needed not including electrics) and the JK I don’t know what the house is actually worth.
With the property market still being crazy, I expect they would relist rather than take a drop of 20/30k.

@Livingintheclouds I'm a property lawyer and I wouldn't touch it with a barge pole.

It's like wildfire and deep rooting.

You will have problems with it when you come to sell and not all mortgage companies will accept even with a management plan.

@maofteens

Bought a house even! *@earsup* it's a requirement by law to disclose it, but I agree there is a hysteria around it which is unwarranted, much like asbestos a couple decades ago and lead paint in the 70s. Obviously these things need to be taken care of properly, but it wouldn't put me off buying.

pleased you went ahead and have things in place....there is an over reaction to it...its classic marketing..find a problem...panic people and scare them...then offer a solution...usually expensive to solve it...its like teenage magazines and the girl with the spots who cant go out..suddenly there are 40 products to deal with the spots...Diet clinics and diet plans...same principals.... or even damp in houses..a whole plethora of treatments and companies which usually dont even work after spending lots of money...