Gardening Answers Knowledgebase
Knowledgebase record #568
I'm having difficulty removing knotweed from my garden. Can you give me advice on how to eradicate it?
I'm sorry to hear you are struggling with knotweed. Manual methods include cutting, mowing, pulling, digging, or covering. Dig surface roots in loose soil. Check frequently for new shoots and dig them up as soon as you notice them. Cut stems close to the ground every two weeks throughout the growing season. After cutting completely, you could instead decide to cover the area of the knotweed patch and the immediate area around it with black plastic or other impermeable material. This is a long-term process, and it may take several years to eradicate the Polygonum. Here are some helpful links on knotweed:
Invasive Knotweeds from the King County Noxious Weed Control Program
Knotweed Biology and Control from the King County Noxious Weed Control Program
Controlling Knotweed in the Pacific Northwest (a large file!)
Japanese Knotweed from the PCA Alien Plant Working Group
There is even a film about this weed, from the Whatcom County Noxious Weed Board!
This link is to a list of slide presentations from the 2007 Western Society of Weed Science Knotweed Symposium.
This presentation describes non-chemical controls, from Seattle Public Utilities.
|Keywords||Polygonum, Noxious weeds|
Need an answer to your gardening question? Ask us directly!
Browse keywords or Search Again:
We are continually adding new questions, so be sure to keep coming back.
April 19 2012 16:02:30