Best to treat lily pads in fall? - Ask Extension
I always heard it is best to treat lily pads with herbicides in the fall because the plant sends the herbicide down to the rhizome and kills it. Is th...
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Best to treat lily pads in fall? #725979
Asked September 22, 2020, 9:05 AM EDT
I always heard it is best to treat lily pads with herbicides in the fall because the plant sends the herbicide down to the rhizome and kills it. Is this true?
Genesee County Michigan
Expert Response
Hello and thank you for using MSU Extension ask and expert with your lily pad question. I do not know if you are asking about a pond or a lake, but I caution that if your body of water is over 5 acres or connected in anyway to another body of water such as a river, stream or other wetland you must seek a permit from EGLE to treat with an herbicide. If it is smaller than 5 acres and not connected to any other larger or contiguous body of water then you can safely treat your own pond.
Herbicides work on the actively growing plant. If you are treating lily pads then it is best to treat them before they stop growing in the fall. If you have fish in your pond then spot treat where you want to control lily pads making sure that you have chosen an aquatic rated herbicide that is safer for the environment.
You can also use mechanical controls such as raking and root removal. Adding something that moves the water such as a fountain or aerator. Waterlilies prefer slow moving or stagnant water near the shore. Combining approaches offers the most effective control. Follow package instructions to ensure safety.
Herbicides work on the actively growing plant. If you are treating lily pads then it is best to treat them before they stop growing in the fall. If you have fish in your pond then spot treat where you want to control lily pads making sure that you have chosen an aquatic rated herbicide that is safer for the environment.
You can also use mechanical controls such as raking and root removal. Adding something that moves the water such as a fountain or aerator. Waterlilies prefer slow moving or stagnant water near the shore. Combining approaches offers the most effective control. Follow package instructions to ensure safety.
Thanks for your quick reply! We’re on a small lake, abt 67 acres.
we have professionals doing the work with proper permitting from the state
a resident challenged me and said lily pads should be treated in the spring. I want to confirm that late summer is the correct time for treatment and not spring.
we have professionals doing the work with proper permitting from the state
a resident challenged me and said lily pads should be treated in the spring. I want to confirm that late summer is the correct time for treatment and not spring.
I also read it’s better for the lake environment to treat after lily pads stop blooming
im the president of our lake association and trying hard to do what’s best for our lake.
thank you!
im the president of our lake association and trying hard to do what’s best for our lake.
thank you!
You are welcome. As the plant is slowing its growth as the water gets colder treating now is okay. Treating anytime the plant actively growing is the important thing to remember as the chemicals are absorbed through the plant's respiration process. Starting in the fall allows time for the chemical to work on well established beds. Lily pads have very strong root systems and it can take up to 30 days to really see an impact. Weakening the root before winter may allow for freeze to further kill the plant. Be prepared that you may need perform a second application in the spring to ensure total control of survivors. FYI killing off lily pads will impact fishing quality of pumpkinseed in your lake.
