Sand saucer look alike

This should have been covered in little rain drops but the rain didn't eventuate.
It is a hydrangea head and reminds me of the sand saucers we used to make for school flower shows.
Unfortunately the little white flowers quite quickly go brown or at least the smallest petals do so it doesn't look very attractive for long. I don't think it is wind, or the dry conditions and certainly not rain causing it. I think it is just a cultural problem.