Although about 23 species of hydrangeas exist in the United States, only five are widely grown here, according to the U.S. National Arboretum.
The different varieties have certain preferences, but all the plants like to be hydrated, said Craig Walker, self-proclaimed “perennial nut” at The Barn Nursery.
“Hydrangeas do like water,” he said. “They’re going to grow better and bloom better if they get plenty of water.”
The color of the hydrangeas also depends upon the variety and even the soil. Limelight hydrangeas, for example, are typically white and can even take on a green tint.
Gardeners can alter soil to affect the blooms’ color. Walker said adding aluminum sulfate to the soil will increase the blue tint, while adding garden lime can make them more pink.