Peonies and Mulch - Ask Extension
I have beautiful peonies. I know they don't like anything else in the bed with them. Can I use mulch to keep the weeds away? Or can I use preen? Or...
Knowledgebase
Peonies and Mulch #906503
Asked June 19, 2025, 10:44 PM EDT
I have beautiful peonies. I know they don't like anything else in the bed with them. Can I use mulch to keep the weeds away? Or can I use preen? Or please suggest options for me.
Hennepin County Minnesota
Expert Response
Thank you for writing.
I suggest mulch.
The active ingredient in Preen is Trifuralin which is a preemergent herbicide. That ingredient should not affect the peonies but has broader ecological effects. https://scholars.okstate.edu/en/publications/trifluralin-4#:~:text=The%20use%20of%20trifluralin%20has,putative%20toxicity%20to%20aquatic%20life.
When you apply mulch, Use sterilized product, without peat. Do not use rubber or plastic mulches. https://extension.unh.edu/resource/garden-mulches-fact-sheet
I suggest mulch.
The active ingredient in Preen is Trifuralin which is a preemergent herbicide. That ingredient should not affect the peonies but has broader ecological effects. https://scholars.okstate.edu/en/publications/trifluralin-4#:~:text=The%20use%20of%20trifluralin%20has,putative%20toxicity%20to%20aquatic%20life.
When you apply mulch, Use sterilized product, without peat. Do not use rubber or plastic mulches. https://extension.unh.edu/resource/garden-mulches-fact-sheet
