Since there are different types, Carol, here's a link for you:
I've grown several varieties of hydrangeas.... I love them, don't you?! There are some for full sun, full shade and in between. Some that bloom on new wood, or old wood. Depending on your location, you'd need to select the right plants. If you wind up with a PeeGee variety, here is a post I wrote on how to prune it.
Hydrangeas need a low pH soil (acidic soil of pH of 5.5, lots of water, and not direct sunlight) to flourish the best.
Hydrangeas seem to do best when they are in partial shade, and of course they needs lots of water!