Japanese knotweed grown in pots – is NOT a method of control.
There is so much information online about Japanese knotweed such as; buying and selling a property with knotweed, does it cause structural damage, how to remove knotweed, legal issues with knotweed, etc. it must be hard to know what to believe.
So when comments such as this one (below) appear that not only advocates planting Japanese knotweed as a “screen between neighbours” but also “planting in a bucket… be sure that the bottom is cut out” (full comment below), we’re here to provide the facts.
“In my area some people use it as a fence. On my clay like soil it’s not invasive. We’ve had it about 7 years and it works well as a screen between neighbours. I know many people in my area who use it the same way and we all just mow over anything that creeps beyond where we’d like it and into the lawn. Planting in a bucket is a good idea – but you probably want to be sure that the bottom is cut out so that it can drink well.”
Firstly, Japanese knotweed should never be used as a screen between neighbours as it will quickly become the neighbour’s nightmare as it creeps onto their property, and could lead to encroachment issues or even legal cases (another one highlighted in the news this week).
Secondly, knotweed planted in a pot (bucket or any container) with holes in the bottom will just allow the rhizomes (roots) to grow through and into the soil. Even if the container is placed on a hard surface area (patio/path), the plant will rapidly outgrow the pot – leaving the issue of replanting it, or worse, discarding it (which is covered by legislation). When replanting, small fragments of the plant’s rhizome could easily be broken off and find their way into soil where it can grow new plants.
Thirdly, do NOT mow over knotweed – this is actively encouraging it to spread. As mentioned above, disposal of knotweed waste must be done professionally which means it has to be taken to a landfill site licensed to receive noxious waste, and by a company holding a waste carrier’s licence. Knotweed (or grass cuttings containing knotweed) must not be discarded in green waste bins, composted or thrown into the wild.
Planting Japanese knotweed in a pot does not ‘contain’ this invasive plant. If you have knotweed and want to know how to remove it, please get in touch and we will be able to advise you.