Japanese knotweed: how do you get rid of it?
Why Japanese knotweed is so persistent, what Belgian law has said since 2025 and the methods that really work in a garden.
Weeding without pesticides: rules and effective methods
Weeds between paving slabs and along paths are among the most frequent requests we receive. Chemical products are now tightly regulated in Belgium. Here is what is allowed, and what really works.
What the law says
Since 2018, private individuals can no longer buy total herbicides such as glyphosate in Belgium. Only a few low-risk products remain freely available. The Regions go further:
- In the Brussels-Capital Region: since 1 August 2025, pesticides have been banned in private gardens, herbicides included. Only low-risk products remain authorised.
- In Wallonia: glyphosate has been banned for private individuals since 1 June 2017, and all pesticides are banned on hard surfaces connected to a sewer or drain, such as pavements and many paths and patios.
- In the Flemish Region: no glyphosate for private individuals, even on paths and patios, and no products at all on the pavement, not even salt, vinegar or bleach.
What about salt or vinegar?
Often presented as natural solutions, they damage the soil and end up in the water. In Flanders, using them on the pavement is in fact banned. Best to forget them.
Methods that work
- Hand weeding or using a joint-weeding knife, effective on small areas if done regularly.
- Thermal weeding, with a flame or hot water, which destroys young shoots without any product. It takes several passes per season, and the flame should be avoided near hedges in dry weather.
- Mechanical brushing of the joints, before refilling them.
- Mulching beds, which deprives seeds of light.
Prevention is better than cure
- Refill the joints between pavers and slabs with polymeric sand or a suitable mortar, which stops seeds from taking hold.
- Cover bare soil in beds: mulch, ground-cover plants or dense perennials.
- Keep a dense lawn, which leaves little room for unwanted plants.
- Clean patios and paths once or twice a year to remove moss and the deposits where seeds germinate.
How we work
We clean patios and paths, weed joints and beds without pesticides, then offer to refill the joints so the result lasts. All in line with the rules of your Region.
This article gives general guidance. Rules change and can differ between municipalities: always check with your municipality before starting work.
