Answer: I should probably mention that in my experience the big leafed hydrangeas including these do best in morning sun or bright dappled light all day; the afternoon sun tends to cause them to wilt and undergo moisture and heat stress. However, if your soil is evenly moist and very organic and humusy and they are well mulched, they may do alright for you there. They also need good winter protection with a position that shelters them from sweeping winds and excessive cold.
The red spots may be due to a soil imbalance and/or an infection. If just a few leaves are affected I would suggest removing them and putting them in the trash, then be sure to clean up all of the fallen foliage from the plants this fall to try to prevent reinfection. Also avoid wetting the foliage and do not handle the plants when they are wet or damp from dew. If however it is extensive or continues, I would suggest you consult with your local county extension to obtain a specific diagnosis of the problem and based on knowing that, determine how to proceed. They may appreciate some photos of the overall plant and closeups or possibly a smaple of the affected foliage enclosed in a clear plastic bag and kept cool so it does not wilt too much in transit. If it is something that requires treatment they will have the most up to date information on what to use, how to use it and the best timing for applying it. I'm sorry you are having trouble with your hydrangeas.
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