Climbing hydrangea (Hydrangea anomala) is a woody vine that produces a multitude of lacy white flowers in early to midsummer. The vine establishes itself slowly, but once the roots are established, the vines can climb quite quickly. Climbing hydrangea requires only minimal pruning to keep the vines under control and remove dead wood.
The vines can be quite heavy and require substantial support and may need pruning for this reason. If there is ample support, climbing hydrangea vines can grow to be 60 to 80 feet tall. The aerial roots will attach onto vertical masonry, brick and wood walls and fences. They can also grow on trees without damaging the tree.
Allow the plant to grow unrestricted until the roots are well established and the vine is climbing. During this time, prune only to remove damaged or dead vines. Climbing hydrangea can take up to five years to establish.
Direct the vines to suitable support materials for climbing. The aerial roots will cement themselves to the support and can be hard to remove, so make sure they land where you want them.
Clip flowers for drying or indoor use as desired or remove spent flowers after blooming. This is not necessary, particularly in tall vines that are difficult to reach, but it does tidy up the plant.
Decide on boundaries for the plant. Prune climbing hydrangeas as needed to control growth in the early fall after blooming is completed. Use clean, sharp clippers or pruning shears to remove vines that are growing out of bounds and restrict climbing hydrangea to the desired area.
Prune away dead and damaged vines, cutting back to a healthy bud.
Remove all debris to the compost heap.