Rose-of-Sharon, Shrub Althea

(Hibiscus syriacus `Blue Bird')

August 1996

Summary:

Foliage: Deciduous broadleaf
Height: 6 to 10 feet
Spread: 3 to 5 feet
Shape: Upright

Green summer foliage. Large single or double flowers bloom in summer. Flower color includes white, red, purple, violet, and blue.

Plant Needs:

Zone: 5 to 8
Light: Partial shade to full sun
Moisture: Wet to moist
Soil Type: Sandy, loam, or clay
pH Range: 3.7 to 7.3

Functions:

Suggested uses for this plant include border and specimen plant.

Planting Notes:

Transplants readily.
Transplant small plants (5 feet or less).
Tolerates wide range of soil pH.
Salt tolerant.

Care:

Blooms occur on current year's growth, so prune in early spring before new growth starts.
Remove one-third of the wood, including the oldest branches and any weak growth, at ground level, annually.

Problems:

Aphids are a problem on new growth.
Susceptible to spider mites in hot, dry locations.
Other problems include leaf spots, blights, Japanese beetle, and white fly.

Alternatives:

Consult local sources, including historic or public gardens and arboreta, regarding cultivars and related species that grow well in your area.

Cultivars of HIBISCUS SYRIACUS :
`Blue Bird' (shown), has blue flowers.
`Diana' has white flowers that remain open at night.
`Helene' has white flowers with a reddish-purple base.

Comments:

This is a large shrub which flowers in late summer when few other shrubs are in bloom.
Single or double flowers range in color from white to red to blue to all colors in between.
Unless older portions of the plant are pruned regularly, the flowers will decrease in size.

Additional Materials:

The PRUNING SERIES videotape can be ordered through your local Extension office.
The following Extension publications are available through your local Extension office or directly from: Virginia Tech Extension Distribution Center 112 Landsdowne St. Blacksburg, VA 24061
#426-500 "Winter Injury to Trees and Shrubs"
#426-606 "Selecting Landscape Plants - Deciduous Shrubs"

This material was developed by Carol Ness as part of the Interactive Design and Development Project funded by the Kellogg Foundation. Mary Miller, Project Director. Diane Relf, Content Specialist, Horticulture. Copyright 1989 by VCE.

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