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What's wrong with my mint #935483

Asked June 14, 2026, 6:14 PM EDT

I have meant in my back Garden in a window box and have found these bizarre holes in it question what is it and how do I address it

Hennepin County Minnesota

Expert Response

Thank you for writing.
Tentatively, this looks like Mint Rust, a fungal disease.
https://www.rhs.org.uk/disease/mint-rust

Send me a picture of the underside of the leaves. 
Are these plants crowded?
How do you water them?
How long have you seen this and has it come on in relation to storms or watering?
Where did you buy your mint plants?
Steve Miles, Master Gardener, Hennepin County, (I am a volunteer human being: not a bot, not AI). I'm an avid gardener but not a degreed or certified horticulturist or arborist. I will do much better if you also send a photograph. I like follow-up questions.  The University' garden soil tests are excellent.  https://soiltest.cfans.umn.edu/testing-services/lawn-garden This is how to find a tree expert.  https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional The Minnesota Landscape Arboretum is a wonderful place to see and learn about plants that grow in Minnesota. https://mngardens.horticulture.umn.edu/minnesota-landscape-arboretum Replied June 14, 2026, 7:40 PM EDT

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