Basically they’re known as invasive species because they are invading! After being introduced into this country from other ecosystems they have been spreading and out competing native plants ever since, devaluing and damaging property in the process. That sounds like the plot of a sinister sci-fi film, a horticultural horror story, they’re just plants, how bad can it be?
In a nutshell, the problem is that both Japanese Knotweed and Giant Hogweed are difficult to kill and can spread rapidly. If removed from site, soils containing viable plant material must be treated as controlled waste and transported and disposed of accordingly. You can also be prosecuted if you cause these species to spread from your property.
Japanese Knotweed spreads by growth or (human or natural) transport of live plant material and can regenerate a new plant from fingernail sized fragments of rhizome (root). The plant grows very quickly (up to 40mm a day!) and can damage physical structures (it grows through and widens cracks and weaknesses in concrete).
Giant Hogweed presents a risk to human health with sap that makes skin photoreactive leading to severe and painful skin irritation. Seriously, just stay away from it. Giant Hogweed spreads from seeds, and a single mature plant can produce up to 50,000 of them which will commonly remain viable in the soil for 7 years but have been found to be viable after 15 years.
There are a range of solutions, feel free to phone us to discuss them on 0131 538 8456.

Guide to Japanese Knotweed
This free eBook will help you learn about Japanese knotweed and how to treat it in the simplest terms. Download it now for free!
Download!
Guide to Giant Hogweed
This free eBook will help you learn about Giant Hogweed and how to treat it in the simplest terms. Download it now for free!
Download!
Knotweed certainly is a pain, on top of the issues with building damage, now in the UK mortgage lenders have started to stop lending for homes with knotweed near them, which is a nightmare for sellers, especially when the knotweed is in a neighbour’s garden.