I planted my bush this summer. It was in bloom when I bought it. Now all the blooms have turned brown. It's been extremely hot here in eastern Kentucky. Should I go ahead and cut off the dead blooms?
All plants do better if one takes the flowers off. An awful lot of energy by a plant is put into seed making (flowers) and once plants have set seed ( older flowers) they kinda take a break, stop making flowers and if we were talking about annuals they simply die. Hydrangeas do better if one prunes the flowers off (then uses them for vases or to dry). To allow the Hydrangea flowers to go all the way to making seed is a waste of energy for the plant.
Absolutely, cut those flowers off! Next year get them off sooner so all that energy that went into making seed would then be used by the plant to grow larger, healthier and even make a few more blooms. Gorgeous as dried flowers!!
From my research and personal experience, the answer depends on the type of hydrangea you are growing. I have mapheads and prune the dead flowers after new growth starts appearing. It apparently protects the new growth from frost. Here is a link to informative article on pruning hydrangeas.
Dead blooms on mophead hydrangeas can, in mild areas, be removed just after flowering, but it is best to leave them on the plant over winter to provide some frost protection for the tender growth buds below. Remove the dead flowerheads in early spring, cutting back the stem to the first strong, healthy pair of buds down from the faded bloom