Real Staying Power: Annabelle Hydrangea and Dusseldorf Pride

My Hydrangea arborescens 'Annabelle' are already in full bloom, and have been the entire month of June. They are supposed to bloom June to September so I'm wondering if they will have the staying power to make it through the heat of July and August.

Similarly, my Armeria maritima 'Dusseldorf Pride' have been giving and giving all summer, and may be sputtering to a finish now at the beginning of July. I bought these from the store this year, so that may be affecting the true bloom time, but nevertheless they have been producing flowers from April 6 to July 2 and they still have a few buds emerging.