Climbing Hydrangea

(Hydrangeaceae - Hydrangea Family)

Form

• primarily a large climbing vine; occasionally found as a slowly spreading groundcover, usually at the base of the existing vine, but sometimes planted specifically as a non-traditional groundcover
• maturing at up to 50' high, but often much shorter
• either a twining and clinging vine growth habit, or an arching and mounding groundcover
• initially a very slow growth rate, but becoming medium to rapid once established

Culture

• full sun to full shade
• prefers moist, well-drained, rich, acidic soils in partial sun, but is somewhat adaptable to poor soils and neutral to slightly alkaline pH soils
• propagated by seeds, rooted stem cuttings, or transplanting of stems that have self-rooted while lying prostrate on the ground
• Hydrangea Family (some sources list it under Saxifragaceae), with few diseases or pests
• commonly available in container form as a young staked vine
• eventually needs some pruning to keep it restricted at its base if it is to be used exclusively as a vine
• if chlorosis of the leaves occurs, a fertilization regimen will likely remedy the plant's nutritional balance, which is probably caused by alkaline soil pH

Foliage

• medium to dark green and glossy on the leaf uppersides
• alternate, broadly ovate, with an acuminate apex and cordate base
• leaf blades are about 3" long, with 2" long petioles
• fall color is a poor chartreuse in October and November

Flowers

• a white outer ring of showy sterile florets surrounds the creamy to green-yellow central fertile flowers
• flat-topped 5" wide inflorescences flower in June and early July

Fruits

• ornamentally insignificant brown capsules lie in a flat plane within the persist outer ring of tan sterile floret remnants
• not especially showy, but the entire flat-topped fruiting structure is persistent into the following season

Twigs

• young stout stems are a rich cinnamon color, exfoliating to show a light brown interior and having many aerial root holdfasts, while prominent buds are a shiny russet
• the curving vertical stems are complemented by many horizontally held stout stems, which give a three-dimensional effect to the structure that supports the vine

Trunk

• exfoliating, light brown, and stoutly branched

ID Summary

• heart-shaped thick leaves arranged oppositely on orange-brown stout stems with aerial holdfasts fully expand before the appearance of the showy inflorescences, which have an outer ring of sterile flowers surrounding the interior, creamy-green miniature fertile flowers
• this slow-growing vine has several terminal-growing, generally upright stems, complemented by the many slower-growing horizontal stems which have most of the inflorescences, and which give the supportive structure a three-dimensional effect

USAGE

Function

• structural cover, primarily used with wooden posts, large trees, or stone walls
• rarely used as a groundcover

Texture

• bold texture in foliage and when bare
• open density in foliage and when bare

Assets

• gives a three-dimensional effect to walls or posts due to its unique outstretched horizontal stems
• showy creamy-white Summer flowers
• lustrous Summer foliage
• shade-tolerant clinging and climbing vine

Liabilities

• very slow to establish
• somewhat open and informal as a vine (but if bold three-dimensional depth is desired for a structural support, this is a true asset)

Habitat

• zones 5 to 8
• native to Japan and China

SELECTIONS

Alternates

• perennial vines that may serve as a structural cover (Actinidia, Akebia quinata, Aristolochia durior, Campsis radicans, Clematis, Hedera helix, Wisteria sinensis, etc.)

Variants

• the species form is essentially the only type that is commercially available

NOTES

Translation

• Hydrangea translates as "water vessel," referring to the cup-shaped miniature fruits.
• anomala translates as "anamalous," perhaps referring to the fact that most members of the genus are shrubs.
• petiolaris translates as "with conspicuous petioles," in reference to the long-petioled leaves.

Purpose

• Climbing Hydrangea is a deciduous vine that gives a three-dimensional depth to supportive structures.

Summary

• Hydrangea anomala subspecies petiolaris is known primarily as a slow-growing clinging and twining vine, with dense glossy foliage that gives a three-dimensional attribute to walls, columns, or other supportive structures due to its lateral branches that extend horizontally for a few feet beyond the supportive structure; the creamy-white flat-topped inflorescences in Summer are an added bonus.