A headache for landlords and tenants alike, Japanese knotweed was brought to the country because of its beauty. Now, however, it’s a thorn in the side of property occupiers and owners.

Japanese knotweed is problematic because of the rate at which it grows, and how seemingly challenging it is to get rid of. As a direct result of these factors, it can be difficult to let a home with Japanese knotweed on the premises and some banks will refuse to approve mortgages, meaning the presence of the weed often knocks tens of thousands of pounds from property prices.

How to know if your property is affected:

Knotweed starts to grow in the spring months. By May, it can be as big as 1.5m, and 3m by June. Over the autumn it dies down and can appear to have almost entirely disappeared over the winter months. But in the height of the summer, where it can grow by as much as 20 – 30cm per day, it’s important to recognise the signs of Japanese knotweed. You might notice:

- Red shoots breaking through the ground

- Heart or spade shaped leaves

- A hollow stem

- Clusters of white flowers that are attracting bees.

Why is knotweed so problematic?

As well as potentially making your investment un-lettable (and knocking tens of thousands off its value), Japanese knotweed can cause several issues.

In its native Japan, the climate and regular ash deposits prevent the weed from growing, although its deep root system allows it to survive. However, in England, there are no such ash deposits and, because the climate is different, it can grow without much of a hindrance. Its strength means that it can even grow through tarmac and brickwork, leading to significant structural problems for houses including subsidence, in extreme cases.

How can you get rid of it?

If you suspect Japanese knotweed is growing in the grounds of your property, try not to panic – there’s several remedies which can ensure this stubborn plant is gone for good.

1.       Dig it all out

If you find knotweed whilst it’s still in its infancy, you can dig it out. However, you must ensure a thorough job is done as it only requires 0.5cm of root to regrow, so make sure it’s completely removed.

2.       Kill it with chemicals

Japanese knotweed can be killed with chemicals, but this can take up to five years, plus professional treatments can cost thousands of pounds. Treatments containing glyphosate help, but be prepared to be committed to killing your knotweed for the long haul.

3.       Cook up a storm

Finally, Japanese knotweed can be eaten. However, if your garden is infested, it’ll take a substantial amount of knotweed compote to solve the problem.

If you do discover Japanese knotweed, then it’s best to call in the experts and see how best to clear it in a safe and responsible way. It’s important to remember that it grows incredibly quickly, so be sure to act immediately.

Leaders Property Management experts are experienced in dealing with issues such as Japanese knotweed. Concerned your buy-to-let property is affected? Speak to our team to discuss our property management levels by calling 0333 363 4005.

Further reading
Landlords, what expenses can you claim for your property?
Top tips for keeping your tenants happy
Leaders’ top tips for first-time or accidental landlords


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