Maybe it's just a little transplant shock. We had some drying winds over the weekend with the sudden ramp-up of temps., so maybe they got a little dry as well. In general, these seem to be plants that need little to no attention.

That sounds like the same thing my Pink Diamond is doing. I moved mine a few weeks ago so that may be the reason. But I have kept it watered so I'm thinking it's not water stressed. I will be interested to see what others have to say...

Some chemicals found in fungicides or insecticides can make hydrangea leaves curl, specially new, small, sensitive foliage. And some tiny pests like spider mites can also make new growth curl. Did you look for tiny pests or did you look elsewhere (in branches, in the soil, under rocks, etc.)? How come you are are using fungicides so early in the growing season? Where are you located and what type of hydrangeas are these? Also, did something happen at about this time last year?

I would try straightening some of the curled foliage to see if you have some common pests called Hydrangea Leaftier or Hydrangea Leaf Curler insects. They are common in the spring. The curling of hydrangea leaves could be caused by one of them. The hydrangea leaftier larva binds two or as many as four leaves together with strands of silk into a cup form and then feeds and rests between them. Pulling apart the leaves will reveal a half-inch-long slender green caterpillar with a black head. The leaf roller insect also causes similar damage, but rolls only one leaf, then feeds and rests within the rolled leaf. Both insects cause unsightly damage, but won’t harm the shrubs. When you see the damage, open the leaves to inspect the contents and squish the buds that you find. If this rates a 1,000 in your EEEEECK Scale, you can also remove the infested leaves (cut the petiole string that attaches the leaf to the stem) and squash the caterpillars. Clean up the ground below the shrubs, too, because the caterpillars drop to the ground and pupate in the summer and emerge as adult moths. This is a problem that can get worse as the moths may return to where they were born to reproduce; if so, the number of infected leaves gets larger (in numbers) with time. Expect some fall leaf color changes now that dormancy approaches. Water if a finger inserted into the soil at a depth of 4-6" feels dry or almost dry; skip watering if the soil feels wet/soggy. Use enough water when watering to moisten the soil down at a depth of 8". Mulching (3-4" past the drip line) can help minimize soil moisture loss. Feel free to deadhead spent flowers at any time but that is not required.