Hydrangea quercifolia aka Oakleaf Hydrangea

Hydrangea quercifolia, or oakleaf hydrangea, belongs to the hydrangea family. This shrub comes from the southeastern United States. Its range includes Georgia, Florida, Mississippi, and Louisiana. Wild plants grow in damp woods, ravines, and along streams. It sheds its leaves and forms a rounded crown. Several upright stems rise from the base. Root suckers help the clump spread beyond its first stems.

Garden plants often reach 4–8 feet [1.2–2.4 metres] tall. Their spread can reach 6–8 feet [1.8–2.4 metres]. Some sources give shorter heights; others report 10–12 feet [3–3.7 metres]. Young shoots have dense, rust-coloured hairs. Older stems shed thin bark and reveal cinnamon-brown layers. The large, dark green leaves grow in opposite pairs. Each leaf has three to seven lobes, much like oak leaves. Fine hairs cover the pale leaf undersides. Fall brings red, purple, orange, and bronze shades. Leaves can stay on into early winter.

White flowers form upright, cone-shaped panicles from May into summer. Small fertile flowers share each cluster with larger sterile flowers. The blooms fade through pink to tan as they age. Old flower clusters can remain on the stems into fall. Butterflies and other insects visit the flowers. Small, brown, dry capsules hold the seeds. These fruits may stay on the plant after flowering. Songbirds eat the seeds. Gardeners also use the flowers fresh or dried.

Grow this shrub in rich soil that drains well. It prefers moist roots and accepts sun or partial shade. Plants in full sun need soil that stays moist. Summer mulch helps keep moisture around the roots. It tolerates some drought but has poor salt tolerance. Sources list USDA zones 5–9 and UK hardiness H5. Cold winters can kill stems and damage flower buds. Young plants need shelter at the colder end of that range. Flowers grow on old wood, so prune just after bloom.

Oakleaf hydrangea suits shrub borders, woodland edges, and loose hedges. Its bark adds winter interest near homes and patios. It needs little upkeep and has few serious pest problems. Aphids, mites, scale, and vine weevils can still occur. Leaf blight, leaf spot, mildew, and grey mould are possible. Deer may browse the plant. Sources warn that plant parts can poison people and pets. Eating bark may cause stomach pain, nausea, and vomiting. RHS also warns of skin allergy. One source labels fruit edible, but this conflicts with poison warnings.