The first time I saw a climbing hydrangea, it was growing its way up the trunk of a majestic oak tree. I’ve been in love with the oddball hydrangea. petiolaris also rose to number one on my must-have plants list.
Climbing hydrangeas are easy to grow. All they need is well-drained soil rich in organic matter. They are not concerned with lighting conditions. A location with morning sun, afternoon shade, filtered light throughout the day, and even full shade are all acceptable planting conditions.
Climbing hydrangea is the answer to a shade gardener’s prayer for a vine that thrives without full sun. It has shiny, dark green, heart-shaped leaves that are beautiful from the time it blooms in the spring until it turns clear yellow in the fall. The exfoliating, cinnamon-colored bark is revealed for winter interest when the leaves fall.
Climbing hydrangeas are also easy to care for. Add a layer of mulch around the plant’s root zone to help retain soil moisture and water in dry periods.
I never prune climbing hydrangeas, but if necessary, most pruning should be done after flowering. Remove dead or damaged branches whenever you notice them. Newly planted vines should spend their energy establishing roots rather than producing new growth, so avoid pruning plants in their first year in the garden.
Climbing hydrangeas grow large, 50 feet or more tall, and get heavy—so be sure to provide support large enough for their massive splendor. They grow their supports in two ways: the vines wrap around them and attach aerial roots or knobs. To encourage a climbing hydrangea to start climbing its support, plant it so it is leaning against the support or tie some branches around the uprights of the structure.
Climbing hydrangeas can also be used as ground cover. Without a structure to climb, the stems scramble across the ground. Wherever the stems come into contact with the soil, roots form and new growth begins.
Because it is slow to establish in the garden, gardeners must be patient for two or three years for its roots to establish. Karma will reward you with rapid growth from then on.
Climbing hydrangeas offer large, fragrant, flat clusters of small, creamy white flowers in early summer. Climbing hydrangeas in full sun will produce more flowers; Vines planted in deep shade may not flower at all. Young vines may take a few years to bloom.
The flowers remaining on the vine will dry out and turn reddish-brown. Leave them for the winter or cut them for use in interior decoration.
Rarely bothered by insects, diseases, or garden pests, climbing hydrangeas are valuable landscape plants for growing across pergolas and fences, climbing trees and concealing unsightly garden structures, extending over stone walls, providing screening, and ground cover in shady spots.
• Diana Stoll is a gardening expert, garden writer, and garden center director at The Planter’s Palette in Winfield. She blogs at Gardenwithdiana.com.