We think we know hydrangeas because we know big shrubs with top-heavy flowers. Meet climbing hydrangea (Hydrangea petiolaris), a member of the same genus, but with a completely different look. This one will attach itself with aerial rootlets to your shady north wall and zoom skyward, creating a bushy curtain of heart-shaped leaves. Lateral branches grow somewhat perpendicular to the ground, creating a bit of a ladder effect. Fragrant white lacecap flowers appear in spring or summer, and the shaggy cinnamon-colored bark becomes an ornament in winter, along with the brown, dried flowers.
Common name: Climbing hydrangea
Botanical name: Hydrangea petiolaris (also H. anomala subsp. petiolaris)
Plant type: Perennial vine
Zones: 4 to 9
Height: To 50 feet
• Sun: Part to full shade
• Soil: Rich, well-drained
• Moisture: Average to moist
• Mulch: Mulch to preserve moisture in the soil.
• Pruning: If the vine needs to be trimmed, cut it back after it flowers.
• Fertilizer: None needed.
• By seed and cuttings
Pests and diseases
• Vulnerable to slugs.
• Powdery mildew, rust, gray mold, and leaf spots can be problems.
• Climbing hydrangea can be slow to get started, but it will grow faster after its roots are established.
• Be sure to provide a sturdy support (such as a wall), as this vigorous vine can get very tall. It also becomes very woody with age.
• Try using climbing hydrangea as a ground cover in shady and partly shady areas—it can cover up to 200 square feet.
• The lacecap flowers are good for cutting and drying.
• H. petiolaris ‘Fire Fly’ has leaves with yellow to cream margins.
• H. petiolaris ‘Skyland’s Giant’ has larger flowers than the species.
All in the family
• Hydrangeaceae, the hydrangea family, also includes the genera Philadelphus (mock orange) and Schizophragma, among others. The Japanese hydrangea vine (Schizophragma hydrangeoides) is often confused with climbing hydrangea.
• The genus Hydrangea contains about 80 species of shrubs and climbers.
Where to buy
• Bluestone Perennials, Madison, OH, 800-852-5243, www.bluestoneperennials.com.
• Hydrangeas Plus, Aurora, OR, 866-433-7896, www.hydrangeasplus.com
• Wilkerson Mill Gardens, Palmetto, GA, 770-463-2400, www.hydrangea.com
(Text by Elizabeth Noll, photo of Hydrangea petiolaris courtesy of Missouri Botanical Garden’s Kemper Center for Home Gardening)