There are many different types of hydrangeas, all of which grow best in plant hardiness zones three through nine. An attempt to grow the flowering bush outside of these hardiness zones may result in damage or wilting from frost or excessive heat.
Ideal temperatures for most types of hydrangeas are in the range of 60 to 70 Fahrenheit. Hydrangeas form buds in the fall that don't bloom until the following spring, so some may be lost or damaged throughout the winter. Hydrangeas can be grown in pots, but they thrive in backyards and gardens, as they need quite a bit of room for root development.