Smooth hydrangeas: What you need to know
Type of flowers: White, round flower heads are the typical bloom, although a new variety scheduled to be introduced in 2010, 'Invincibelle Spirit', is pink and is a rebloomer.
Where to plant: Grow in sun to part shade.
Recommended types: Try: 'Annabelle', 'Hayes Starburst', White Dome.
Zone: Zone 4 ('Invincibelle Spirit' is hardy to Zone 3).