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Rhododendron 'Glacier'
glacier rhododendron
Garden hybrid origin (B.Y. Morrison, USDA Glenn Dale MD; purest white Glenn Dale azalea; bridges Kurume and Southern Indian types)
Overview
Rhododendron 'Glacier' is a semi-evergreen to evergreen azalea reaching 3-5 feet (0.9-1.5 m) tall with a spread of 3-5 feet (0.9-1.5 m) and a compact, dense, upright to rounded habit. A Glenn Dale hybrid (developed at the USDA Plant Introduction Station, Glenn Dale, Maryland by B.Y. Morrison), it produces single, funnel-shaped flowers 2-2.5 inches (5-6 cm) wide in pure white with a faint green tinge in the throat, densely covering the plant in May. The small, elliptic leaves 1-2 inches (2.5-5 cm) long are glossy medium to dark green. Growth rate is moderate. Hardy to zone 6. The Glenn Dale hybrids were bred to fill the gap between the small-flowered Kurume azaleas (hardy but small flowers) and the large-flowered Southern Indian azaleas (large flowers but tender). 'Glacier' is the purest white Glenn Dale.
Native Range
Rhododendron 'Glacier' is a hybrid of garden origin, developed by B.Y. Morrison at the USDA Glenn Dale station, Maryland.Suggested Uses
Planted in mass plantings, borders, or foundation plantings at 3-4 foot (0.9-1.2 m) spacing. Pure white. Glenn Dale hybrid. Semi-evergreen. Not suitable for alkaline soils, full sun, or dry conditions.How to Identify
Appearance
Size & Dimensions
Height3' - 5'
Width/Spread3' - 5'
Reaches mature size in approximately 6 years
Bloom Information
Single funnel-shaped pure white flowers 2-2.5 inches (5-6 cm) with faint green throat tinge, densely covering the plant, May. Bloom duration 3-4 weeks.
Detailed Descriptions
Flower Description
Pure white with faint green throat tinge; single funnel-shaped 2-2.5 inches; densely covering plant; MayFoliage Description
Glossy medium to dark green; small elliptic 1-2 inches; semi-evergreenGrowing Conditions
Sun Requirements
Requires 3-6 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Plant in partial shade in moist, well-drained, acidic soil (pH 4.5-6.0). Hardy to zone 6. Semi-evergreen—may lose foliage in cold winters. Mulch to protect shallow roots.Pruning
Prune lightly after flowering to shape. Avoid pruning after July—next year''s buds form in summer.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
late spring
Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons