THE NATIVE HYDRANGEAS
Smooth Hydrangea (Hydrangea arborescens): The Northeast’s smooth hydrangea was first “discovered” by European botanists in Pennsylvania but has a broad range, extending from a chilly zone 3 to warm but non-tropical zone 7. Smooth hydrangea has beautiful white lace cap flowers; it is a shrub of medium height that naturally likes rocky slopes and stream sides.
Picture: A totally gorgeous, totally graceful native smooth hydrangea grows at the forest edge, next to a pond at the Bartlett Arboretum, Stamford CT July 2005. The smooth hydrangea only comes in white.
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Smooth hydrangea doesn’t do drought well; it does full sun only with plenty of water. It does needs good light and some pruning to keep it from looking full and healthy. It root-suckers, so, over time, it forms a nice clump.
Smooth hydrangea is supposed to be a “new wood” flowering type but is subject to winter damage in the north. It is best pruned in the spring. Pruning back to a foot or two from the ground each spring is safe.