Some of the leaves on my bottlebrush buckeye are curling/wilting. Do you know what might be the matter and how I should treat it?
What a lovely shrub! You are very fortunate to have chosen a native plant with few or no disease problems. However, based on your query and the attached photo, you may wish to consult the sources below.
The first site listed below suggests leaf scorch as a potential issue.
Soil amendment may help, but the shrub tolerates alkaline as well as acidic pH.
The second site does warn us that the shrub is NOT drought tolerant, so make sure you have lots of moisture in the soil. Water consistently for best health. Scroll down the pages in the Clemson university site to problems, and read the solutions carefully there. You will note that the wilting could be leaf blotch caused by the fungus Guignardia aesuli. The remedies may be limited in Ontario. Your potential development of the fungus may be understandable this year with the generous rainfalls we have experienced in the GTA lately.
https://www.wildflower.org. and type in Aesculus parviflora in the search tab