I have three hydrangea plants (2 "Limelight" and 1 "Quick Fire"), and I've recently noticed that the leaves on all 3 are turning rust-colored on scattered parts of the shrubs. They are not rust spots; rather, they are large brown patches. A few of the leaves have curled up. They are all planted in sites that definitely receive full sun (especially in the afternoon), and we've been having unusually long spells of warm weather for where I live (central Alberta), with the last three weeks or so very warm and sunny. The soil underneath the mulch is moist, but is this simply a case of too much hot sun and not enough moisture? I thought that these particular varieties did well in full sun. Any comments/suggestions would be much appreciated!
