Master Gardeners are frequently asked about care/pruning of Hydrangeas. The answer varies depending on type of hydrangea; there are 4 common types.

All hydrangeas grow best in rich, medium moisture, well drained soil in part shade.

All pruning should follow the five Ds. Prune out dead, diseased, damaged, defective, and dangerous stems when you see them.

Hydrangea macrophylla commonly called Bigleaf Hydrangea.

These are the pink and blue hydrangeas common to British Columbia and rare in Northumberland County.  Colour of blooms depends on acidity of soil; blue in highly acidic soils  and pink in alkaline soils. There are also white varieties. Hydrangea macrophylla  are winter hardy to Zone 6 but may grow in zone 5 in a sheltered location with winter protection.

They require little pruning, but pruning for shape if necessary,  should occur immediately after flowering as they bloom on old wood.

Hydrangea paniculata  commonly called Hardy Hydrangea or Pee Gee Hydrangea

This is a very common  hydrangea in Northumberland County, one of the most winter hardy ones. Thrives in urban conditions. It is a perfect 3 season plant with white  cone shaped summer blooms turning pink/red in fall and then tan in winter. There are many, many cultivars.

Hydrangea paniculata is a large multi stemmed shrub and is best pruned to keep it compact. Since it blooms on new wood pruning should take place in late winter/early spring. Hydrangea paniculata can be cut back severely to rejuvenate.

Hydrangea quercifolia  commonly called Oak Leaf Hydrangea

This is a broad rounded suckering shrub with panicles of white pyramidal flowers in summer. Often grown for its spectacular fall foliage.

Not as common in Northumberland County, it is hardy  in zones 5-9

Flowers bloom on old wood and pruning is seldom required, but should be done right after flowering if necessary.

Hydrangea arborescns commonly called wild hydrangea.

Annabelle is the most commonly seen variety but others are being developed.

Very common in Northumberland County and is cold hardy to zone 3.

Annabelle bears large, rounded, stunning ,white  blooms that last from June through September. In fall flowers turn tan/brown  are often left in place for winter interest.  Flowers are frequently used in fresh and dried arrangements.

Hydrangea arborescens  blooms on new wood and should be cut back to about 6 inches in fall or late winter.

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