Knowledgebase

Question about this plant/weed #804884

Asked August 05, 2022, 10:28 PM EDT

Hello, I wanted to ask about this plant/weed that I'm including photos of. You quite often see this plant growing low to the ground and it seems to Thrive during dry weather like we are having now. Farms are a place where you see it quite often but these pictures were taken at a Minneapolis Park. Can you tell me what this is? Is it native or invasive? Might it be an alternative plant for a yard? It seems to be much softer than grass, especially now. We have a yard with many oak trees in the ground seems to be chronically rough and grass doesn't have the best. Thanks, Owen

Ramsey County Minnesota

Expert Response

Hi, thanks for the question. Always nice to have a challenge late in the evening.

This is the dreaded Prostrate Knotweed (Polygonum aviculare). It rears its ugly head during late July and August. It is an annual plant which means it will die off within the next six weeks or so. But prior to doing so, it will release an unbelievable number of seeds that will be dispensed by wind and birds. These seeds will then subsequently germinate spring 2023. If you look closely at it, you will see its characteristic red stems. See:

https://apps.extension.umn.edu/garden/diagnose/weed/broadleaf/creeping/pknotweed.html - :~:text=Leaves are small, narrowly oval,Long, thin tap root

http://www.minnesotaseasons.com/Plants/prostrate_knotweed.html

Thanks for using our forum.

Steve Hedman Replied August 06, 2022, 12:01 AM EDT
It's a bummer that it's considered so annoying and is just an annual. Interesting that it only grows for part of the summer. It's such a nice soft plant and grows low and we thought it might be a lawn alternative similar to what some people are doing with clover. Thanks for such a quick response!
Owen

Ask Extension wrote on 8/5/2022 11:01 PM:
Owen and Heidi Replied August 06, 2022, 1:26 PM EDT


Thanks for your response.  Annoying is always in the mind of the beholder.  Thanks again for your thoughts.

Steve Hedman Replied August 06, 2022, 5:07 PM EDT

Loading ...