Slow to settle in, climbing hydrangea quickly grows to 60 to 80 feet in height once it establishes itself. The vine attaches itself by means of rootlike holdfasts similar to those on ivy, so it can grow up any surface. If unsupported, climbing hydrangea grows into a rounded shrub. These vines are hardy in U.S. Department of Agriculture plant zones 4 through 8, although they struggle in the high temperatures of zone 8. They grow best in rich, well-drained soil in full sun or partial shade.
Climbing hydrangeas have glossy, dark green leaves in the spring and summer. The heart-shaped leaves are 2 to 4 inches long, nearly as wide, and come to an acute point on the end. The undersides of the leaves are lighter, giving the plant a sparkling appearance when the wind rustles the leaves.
In fall, climbing hydrangea leaves persist on the vine until late in the season. Normally they detach, or abscise, while still green, but in some years the foliage turns a clear yellow. While climbing hydrangeas are normally pest-free, it's always a good idea to clean up leaf litter in the fall so that insects and disease spores don't overwinter near your plant.
Climbing hydrangeas do not keep their leaves in winter, but the foliage does stay on the plant until late fall. The falling leaves allow you to appreciate the beautiful exfoliating bark, which is hidden during the rest of the year.