Smooth Hydrangea (Hydrangea arborescens)-Hort Answers - University of Illinois Extension
University of Illinois Extension

University of Illinois Extension

Hort Answers

Shrub

Smooth Hydrangea
Hydrangea arborescens

Smooth Hydrangea form
Smooth Hydrangea form
 
Features
Large clusters of white flowers, early to mid-summer; yellow autumn color may develop, but is not reliable. 
 
Culture
Best in partial (to full) shade, but will tolerate full sun if watered regularly; moist, well-drained soil is preferred; tolerates alkaline soils. 
 
Cultivars
  • 'Annabelle' - Large white flower clusters (up to 1 foot across).
 
 
Mature Height
3-5 Feet
 
Size
Small
 
 
Mature Width
3-5 Feet
 
Mature Form
Rounded 
 
Native To:
United States (and Illinois) 
 
USDA Hardiness Zone
4 - 9 
 
Soil Conditions
Moist, Well-Drained
 
 
Tolerance
Alkaline Soil
Salt
 
 
Exposure/Light Requirements
Full Shade
Full Sun
Partial Sun/Shade
 
 
Uses
Border
Foundation
Massing
Specimen
 
 
Foliage Color
Green
 
 
Fall Foliage Color
Green
Yellow
 
 
Pests and Problems

Environmental Damage

Fungal Disease


Additional pests and problems that may affect this plant:

Insect and disease problems are possible, but are not common.
 
Additional Notes
This shrub often dies back to the ground in northern climates. This does not affect flowering as the shrub flowers on new growth produce in spring.

 

 
Related Resources
Home, Yard & Garden Pest Guide
Illinois Commercial Landscape and Turfgrass Pest Management Handbook
U of IL - Distance Diagnosis through Digital Imaging
U of IL - Plant Clinic