What is a pia hydrangea?

Hydrangea macrophylla, also called Pia, is a registered dwarf, mophead hydrangea cultivar. It is a deciduous bigleaf hydrangea with showy, pink blooms when grown in alkaline soils. In acidic soils, the blooms range from blue to lavender.

Pia hydrangea blooms from July to August in U.S. Department of Agriculture hardiness zones 5 to 9. It has a rounded habit and grows from 3 to 6 feet tall and wide. It prefers shade and blooms on the previous season's wood, so it should only be pruned after blooming. Pia has no serious disease or insect problems. It is propagated by softwood cuttings taken in early summer or by hardwood cuttings taken in winter.