All hydrangeas will turn brown if they wilt too many times in hot weather. Water these shrubs deeply every few days in the heat of the summer (note that hand watering isn’t deep enough) and mulch around plants to hold moisture in the soil longer.

What do you do when hydrangea leaves turn brown?

Problem: On a rare occasion, you might have a problem with pests like aphids or scale insects. These will result in your leaves shrivelling up and turning brown. Solution: The solution is to use a direct stream of water to physically wash the pests off the leaves.

Why is my hydrangea leaves turning brown and drying up?

If your hydrangea leaves have started to wilt its usually an environmental problem such as to much sun as they prefer a shady position or not enough water, especially when grown in containers. Applying too much fertiliser can also cause the leaves and flowers to wilt.