Q.Why Is One Of My Endless Summer Hydrangea Plants Wilting? Please Help!
I live in Waltham, MA. I have seven Hydrangea plants on the East side of my house. I live in Waltham, MA. They get morning sun and afternoon shade. One of the seven plants is wilting badly and won’t stand up even after watering. I have seen the plants wilt but they usually go back to normal after they are watered and the temperature has cooled. But this one has been in this wilted state for a week. I should mention that i planted all of them at the same time in September 2019. They all flowered on old and new wood as expected and were beautiful in June and early July. We have had a few hot days in the 90s but the temperature goes down to 69-70 at night. I also make sure I don’t over water the plants. Is this plant dying? Is there anyway I can save it?

Certified GKH Gardening Expert
No, Hydrangeas will wilt for quite a few reasons. They will often come back just as fast once the environmental problem that is causing it subsides.
Despite the heat, make sure that the top in to 2 inches has a chance to dry out, thoroughly, between waterings. Overwatering can cause drooping by suffocating roots.
Alternatively, not enough water can cause this, as well. I do not think that this is the case, here.
Most commonly, just a little too much sun will do it. The solution may be to erect a shade cloth during some of the morning sun.
Here is an article that will help with this common problem:
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/drooping-hydrangea-plants.htm