Hosta and Joe Pye Weed leaves are being eaten by something from ground up. Just planted this spring. Trying desperately to save new diy landscaping project this spring. Have had over 12 inches of rain in 5 weeks. Both plants are in partial sun/shade area right next to house on the walkway. Live in IN with horrible hard clay. Planted with self fertilizing potting soil with mulch on top. Please help me save these beautiful plants!
Something Eating Plants
Certified GKH Gardening Expert
The yellowing leaves are most likely the results of the heavy rain. The plant then becomes stressed.
Insects and fungus can certainly be an issue and the damp weather seems to make things worse.
Neem Oil is a good treatment as it acts as both an insecticide and fungicide.
Here is a link with more information.