Maiko Mountain Hydrangea. This has to be the "cutest" little Hydrangea around. It sports the smallest mopheads that I have ever seen, about the size of a tennis ball. This species is more cold hardy than the larger growing "macrophylla" types. Mine usually stay in the neighborhood of 18" in height with a somewhat wider spread. It is happiest in filtered sun with uniform moisture and good drainage. It's lax stems work beautifully hanging over a wall.
Zones 5-9