If you’re thinking about selling your home, do yourself a favour and don’t buy a house that has had Japanese knotweed problems on it without doing your due diligence first.
This invasive weed can be dangerous to your health and your home’s foundation. If you don’t take the time to inspect your potential home thoroughly before putting it on the market, you may end up with a home that won’t sell or be worth the asking price.
If you’re looking for a new home, but are concerned about the presence of Japanese knotweed problems in the area, then this article is for you. We’ll explore what happens when you buy a house that has had Japanese knotweed problems before and offer tips on how to avoid being affected by it yourself.
Japanese knotweed can be devastating to your property’s value and health if not dealt with immediately. It spreads through underground rhizomes and shoots up above ground quickly as well, so it can do major damage before anyone notices.
Japanese knotweed problems
Here are a few reasons why Japanese knotweed problems are so problematic and what you can do to avoid them when selling a property with it.
One reason that Japanese knotweed is such a deal-breaker is that it’s a common problem. It shows up everywhere from the southern United States to New Zealand and is especially prevalent in the UK.
It has spread into more areas, as people have started to grow it in their backyards without realizing the dangers it poses.
In the case of the UK, Japanese knotweed problems have even gotten so bad that in some areas, the government has had to reintroduce regulations in an effort to halt the spread of the weed.
When you deal with a real estate agent who isn’t familiar with this type of property, you run the risk of letting a potential buyer down when they mention it.
Another reason why it can be such a deal-breaker is that it can destroy the foundation of a house. It can be so invasive that without intervention, your home could crumble. Even when your foundation is protected, it will be vulnerable to wind and rain.
That’s because when Japanese knotweed begins to grow, it starts at the top. Because it has spread so quickly and broadly, it has already reached much of the soil in your backyard before it has a chance to weaken and break down any structure or settle on the foundation.
One final reason why it can be such a deal-breaker for you when buying a property with Japanese knotweed problems is the cost. The costs of treating the property will be expensive, and because there is not a very strong control over the spread of the weeds, the costs are likely to keep on going up.

Prohibitive costs of buying a property with Japanese knotweed problems
When you add that to the already high costs of treating a property, it’s easy to see why it’s considered a deal-breaker. On top of that, you run the risk of having the property foreclosed upon when the knotweeds aren’t being treated.
If you have no choice but to deal with Japanese knotweeds when selling your home, then you need to focus on getting rid of them as soon as possible. The fastest and easiest way to eradicate them is with a herbicide.
Before you do anything else, however, you should check with your local planning office for recommendations on the best type of herbicide to use for your particular situation. Some herbicides are safe to use on your own, and others require that you apply them by hand or spray them directly on the weeds.
Herbicide treatment
If you’re going with a herbicide that’s available from a retail agent, you’ll probably want to choose one that’s readily available at your local garden store.
There are some herbs that are invasive enough to warrant using a different type of herbicide than one that’s sold over the counter. When you choose a specific herbicide to use for your property, don’t expect the weed to just die and vanish.
That would just mean the end of your garden. Instead, get the herbicide to kill the plant so it won’t grow back. You can also use a commercial herbicide for this kind of situation, which is designed to be more concentrated than the sorts available for your home.
Once the herbicide is applied properly, the knotweeds should be killed within a few days to a week. However, even if they stay dead, you should take care not to pull them up.
You should instead carefully remove the dead plant from the soil, as well as any other plants or bushes that were affected by the weed.
Many lenders will not finance properties that have such a problem. In fact, you may even find that you’ve declined a loan in order to purchase the property back from these lenders.
Final thoughts
Of course, you can take steps to eradicate any knotweed in your garden before you actually attempt to get rid of it. The best advice is to pull any weeds in the garden, even the ones that aren’t fatal, and to do this in the late summer or early autumn.
This will ensure that no problems arise with your property in the meantime. You should also try to keep on top of the weed problem by using a weed barrier, a type of membrane that will be effective against Japanese knotweed problems, along with other garden products.
Want to know more about how to remove Japanese Knotweed problems?
Knotweed Removal aims to provide the most up-to-date information, help and advice for YOU to make informed decisions. If you are unsure or uncertain about how to proceed, please reach out to us and we will gladly come back and advise you as best we can.
Governmental advice can be found here and the UK law covering the removal of Japanese Knotweed as stated under the Wildlife and Countryside Act 1981 can be found here.
The best means to contact us is via our email – hello@knotweedremoval.tips
Do not forget we have a library of blogs covering many areas relevant to Japanese Knotweed, our free downloadable How-to Guides and Product Reviews on the latest methods being employed to eradicate or remove Japanese Knotweed.
Knotweed Removal, UK
- This exclusive twin pack and 9L Watering Set is everything you need for clearing weeds from paths, patios and rives including areas of tarmac, concrete and block paving.
- Kills tough weeds and their roots including: Ground Elder, Nettles, Docks, Couch Grass, Japanese Knotweed, Brambles, Bracken & Ivy.
- Each box contains 3 x 8g Simple ready measured soluble doses and treats up to 75sqm. Apply at any time when weeds are showing green leaf and are actively growing.
- Sold with our durable 9L or 2 gallon capacity galvanised steel watering can with removable brass rose. Colour cannot be guaranteed. Watering can will be randomly picked and despatched.
- Keep children and pets away from treated areas until the spray has dried.
- Kills ivy japanese knotweed, saplings, brambles and nettles to the root
- Kills up to 16 tree stumps
- Contains a reusable pipette for specialist treatment of japanese knotweed
- Kills the roots so weeds don't come back
- Degraded in the soil by micro organisms
- Ideal for clearing weeds from paths, patios and rives including areas of tarmac, concrete and block paving.
- Kills tough weeds and their roots including: Ground Elder, Nettles, Docks, Couch Grass, Japanese Knotweed, Brambles, Bracken & Ivy.
- Each box contains 3 x 8g Simple ready measured soluble doses and treats up to 75sqm.
- Apply at any time when weeds are showing green leaf and are actively growing.
- Keep children and pets away from treated areas until the spray has dried.
- Fast action ready to use weed killer that kills the weeds and roots with visible results in 1-2 days
- Kills most garden weeds with a single application; up to 10 minutes of continuous spray when using 5 L option
- Children and pets need not be excluded from treated areas (once dry)
- The Pump N Go pressure sprayer is easily refillable, a one- touch trigger prevents hand fatique and extendable lance avoids bending.
- Degraded in the soil by micro organisms
- KILLS ROOTS AND WEEDS - contains 72g/l glyphosate (acid equivalent) present as 79.2g/l of the ammonium salt of glyphosate
- TOTAL WEEDKILLER: For larger trees and shrubs to treat freshly cut stumps. For smaller shrubs and woody weeds (such as brambles) below 1 metre in height, cutting is not always necessary and the product can be diluted and applied as an overspray. For other annual and perennial weeds apply as an overspray.
- DILUTION: 1 x 100ml Sachet to 900ml Water - Makes 1L of Weedkiller - Coverage up to 66sqm per sachet
- LARGE COVERAGE: For perennial grasses, broad Leaved weeds and other woody weeds (e.g. brambles). 1 Litre treats up to 66 square metres.
- BIODEGRADABLE in soil