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Hydrangea fungus #929682

Asked April 26, 2026, 2:46 PM EDT

Happy spring! Cutting back some hydrangea bushes and found this fungus on them. Wondering what it is and if there is any treatment for it. Thank you, Michelle

Olmsted County Minnesota

Expert Response

This is a poisonous mushroom.   They can signal a fungal infection.  I would cut out the infected stems and dispose of them.  The fungus is usually caused by too much moisture. Remove the mulch under the plant and check for fungus underneath.  Move the mulch away from the stems of the plant and allow air to get to them.  Keep an eye out for more and apply a copper-based or neem oil fungicide to the affected area if it comes back.  Good luck!

Deb Kroon Replied April 26, 2026, 7:57 PM EDT

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