Marianne's Response
My Hostas Have Problems
What is happening to my Hostas? This appeared suddenly and has affected every flower bed I have. This particular Hosta is in a bed that was planted last year (it’s where I noticed the damage first). I added an Astilbe in here this spring. And now all the other plants I put in the spring have the same thing going on, including my Hydrangeas and Day Lillies. There is one flower bed planted last spring that is ok and I have not added or taken anything out.
Posted by Amber Staudacher on June 9, 2020
Marianne's Response
This looks like Southern Leaf Blight of hosta. This fungus appears about 10 days after heavy rain and infects hosta that may have been planted too deep or in soil that is infected with the fungal spores. High humidity, rainy days and warm weather causes the outbreak. Pull back any mulch to increase air circulation, remove infected leaves immediately, do not overhead water or water at all for awhile and clean your tools to stop the spread of the infection. You can try a fungicide spray but until the weather changes or you replace the heavy soil with soil that drains well this fungus will be hard to control. Don't give up. There are plants such as coral bells that are resistant to this soil fungus. Keep growing, Marianne Binetti
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