Today I discovered the same damage to my apple tree and climbing hydrangea. Photos attached. Please let me know what you think this is and how it should be treated.

Hello,

To clarify the timeline, you had your yard sprayed with the two chemicals on May 4th and you noticed the symptoms in mid May?

When were the photos taken?

The products are fungicide and insecticide respectively.

Some of the damage looks like aphids, speckled leaves, leaves curling downward, and sticky. Look under the leaves of the newer growth of the azalea, apple, rose, and stewartia. Do you see aphids or other insects?

If yes, try insecticidal soap or neem oil. These insecticides kill aphids and other soft bodied insects on contact.

Overall, to me it looks like something may have gone wrong with the spray on May 4th and/or over fertilization and/or herbicide damage.

Leaves that would have been new about a month ago are looking damaged. The newer growth is looking better (except the stewartia).

Did you also fertilize these plants this spring? What kind of fertilizer and how much.

When did you add the compost mulch? It could have had a lot of plant-available nutrients or contaminants.

Did you or your landscape company apply herbicide this spring?

Regardless of the cause of plant damage, I would take a wait and see approach. It takes time of plant damage to unfold, especially from non-living cause such as the ones mentioned above.

Feel free to send me more pictures in about a month. The damage may lessen or worsen in that time and provide more clues to diagnose the situation.

Also, none of the damage looks catastrophic so waiting to see what happens will not lead to long-term damage of your plants.

Weston