Japanese knotweed is an invasive plant that has caused a lot of trouble in the UK. Live cases have risen by almost 28% in the past five years, and it's been estimated that Japanese knotweed robs the British economy of £41 million each year.
If you find Japanese knotweed growing on your property, it's important to get it under control ASAP - leaving it to grow unchecked can reduce the value of your home, and you may even find yourself on the wrong side of the law if you permit the plant to spread into the wild.
So when it comes to dealing with Fallopia japonica, time is of the essence. That being said, you shouldn't try to tackle this plant yourself unless you know exactly what you're doing; Japanese knotweed is a tricky customer, and most amateur attempts to eradicate the plant just end up spreading it further.
To help you make the right decisions, here's a quick overview of what to do - and what not to do - when you discover Japanese knotweed on your property.
What to do
- DO make sure it really is Japanese knotweed. There are quite a few plants that look similar to knotweed, so look closely before you take action. If you're not sure what to look for, read our Japanese Knotweed Identification Guide or contact Taylor Total Weed Control and we'll send one of our invasive weed specialists to confirm the plant's identity.
- DO seek expert advice. There are several different ways to deal with Japanese knotweed, and physically removing the plant from the soil often isn't necessary. In most cases, we instead recommend a course of herbicide applications followed by a period of monitoring to make sure the knotweed doesn't grow back; this treatment programme, combined with an insurance-backed guarantee, should be sufficient to reassure buyers and mortgage lenders if you decide to sell your property in the future.
- DO talk to your neighbours. When Japanese knotweed spreads from one property to the property next door, it can result in conflict and even legal disputes between neighbours. If you've discovered Japanese knotweed in your garden, it's a good idea to inform your neighbours and let them know what you're planning to do about it. Opening the lines of communication early on will help to minimise the risk of quarrels further down the line. For more information, see How to Resolve a Japanese Knotweed Dispute with Your Neighbour.
What NOT to do
- DON'T attempt to remove Japanese knotweed on your own. Fallopia japonica should only be removed by trained experts; if even a single fragment of the plant's rhizome root system finds its way back into the soil, it can grow into a whole new plant, so this job has to be done with the utmost care.
- DON'T leave the plant to grow. You might be tempted, upon discovering Japanese knotweed in your garden, to do nothing at all - but knotweed grows very quickly, and if you don't take action, there's a risk that the plant will spread into your neighbour's garden or into the wild.
- DON'T lie about Japanese knotweed when selling your home. If you wish to put your property on the market, you will need to fill out a TA6 form, which includes the following question: Is the property affected by Japanese knotweed? Some sellers have answered this question with a 'No' or 'Not known' in order to speed things along, but if you are aware of a past or present knotweed infestation on your property then failing to declare it can get you in trouble later on. Japanese knotweed misrepresentation cases have risen by 25% in the past year, largely as a result of unscrupulous sellers keeping quiet about their past battles with Fallopia japonica.
If you've discovered Japanese knotweed on your property, contact Taylor Total Weed Control to arrange a free survey.
Our Japanese Knotweed Treatment Plans >
Getting your property treated for Japanese knotweed can sometimes be a lengthy process! Herbicide is the most common method for dealing with Japanese knotweed.
If you know you have Japanese knotweed on your property and decide to go ahead and treat it with herbicide, here are a few do’s and don’ts to help ensure success.
Knotweed Treatment Do's:
- DO always read the management plan thoroughly – if there’s anything you don’t understand, contact us and ask
- DO leave the knotweed alone and allow the herbicide time to work.
- DO cut down the dead canes between January and February and allow them to dry out on site.
- DO quarantine the contaminated area to prevent traffic unintentionally spreading the plant material across your property.
- DO report any new growth that is outside of the treated area.
Knotweed Treatment Don'ts:
- DON'T flail or mow the knotweed, as this can cause it to spread
- DON'T intentionally spread the knotweed stems and crowns
- DON'T spread any soil contaminated with the knotweed rhizomes (any soil obtained from within 5m of a Japanese knotweed plant could potentially contain rhizomes, which are highly regenerative and will readily grow into new plants).
- DON'T chip Japanese knotweed material – this will not kill the knotweed, and if you spread chipped knotweed material it could cause the Japanese knotweed to regrow.
- DON'T add Japanese knotweed material to compost.
- DON'T leave it for later – if Japanese knotweed appears on your property, treat it immediately!
- DON'T allow it to spread in any other way; if you let/cause Japanese knotweed to spread you could be guilty of an offence under the Wildlife and Countryside Act 1981.
- DON'T cut or trim treated knotweed plants.
- DON'T attempt to treat the knotweed yourself with herbicide.
- DON'T disturb the ground within 2-3m of any Japanese knotweed plant.
- DON'T dispose of any knotweed material (including soul from within 5m of any knotweed plant or previously contaminated area) off site.
- DON'T allow access or traffic through a contaminated area.
READ MORE: What Does Japanese Knotweed Look Like When It First Comes Up?