Smooth Hydrangea plant profile
Hydrangea arborescens
A perennial shrub for full sun.
Last updated .
When to plant
When to plant Smooth Hydrangea
Plant this deciduous shrub while dormant, in fall or early spring. Extension guidance rates fall (early enough for roots to establish before the ground freezes) as the best time and spring, just before growth begins, as the next best.
The calendar shows this cited seasonal window as an approximate band. It does not convert the season into frost-adjusted dates.
Open Smooth Hydrangea in my garden calendarShows the source-backed planting season, not frost-adjusted dates.
Growing conditions
- Sun
- Full sun
- Soil pH
- 5 to 8
- Lifecycle
- Perennial
- Spacing
- 36 to 60 in apart
- Hardiness
- Zones 3a to 9bFind my hardiness zone
Common problems
Watch for these
Also watch for: leaf spot, bud blight.
Evidence trail
Evidence behind this profile
Original extension and institutional publications behind the planting, care, and safety facts on this page.
- Hydrangea arborescens (Smooth Hydrangea)
North Carolina Extension Gardener Plant Toolbox (NC State Extension). Supports general reference. Checked 2026-06-18.
- Planting Shrubs Correctly (HGIC 1052)
Clemson Cooperative Extension, Home & Garden Information Center. Supports planting reference. Checked 2026-06-18.