Water plentifully as often as necessary to keep potting mixture thoroughly moist. Never allow the soil to dry out. If the soil does dry and the plant wilts, immerse the pot in a bucket of water until the root ball is thoroughly soaked. Note that blossoms that have been allowed to wilt may not recover.
Flowers can last up to eight weeks if kept in a cool location (between 55F and 60F degrees). In average household temperatures blooms will last three to four weeks.
Bright light is best but make sure to keep hydrangeas out of any direct sun.
Feed regularly with an all purpose fertilizer for as long as the plant remains indoors.