I received two hydrangea bushes for my birthday. One has 11-13 blooms, the other has nine blooms. I have had them out on the deck during the day but bring them in at night, especially if it gets too cool. Fortunately, we have had beautiful weather since I received them. No instructions came with them, so I don't know how much water to give them or whether to leave them sitting in water or empty them before bringing them in the house. The blooms on the larger plant are dying off around the edges.
Care of Hydrangea Bushes
Certified GKH Gardening Expert
If you keep them in pots, you will need to treat them like houseplants. Right now, water only when the soil on top is dry. When the temps rise and you leave them outside all the time, you will find you will need to water them daily. The brown edges on the blossoms are from over watering.