Rhododendron, Genus, prinophyllum, Species,
- Genus & species
early azalea
Overview
Rhododendron prinophyllum is a deciduous shrub reaching 4-8 feet (1.2-2.4 m) tall and 4-8 feet (1.2-2.4 m) wide, occasionally to 10 feet (3 m) in shaded sites. Stems are upright and loosely branched, forming an open, rounded outline. Leaves are elliptic to obovate, 1.5-3.5 inches (4-9 cm) long, blue-green above with soft hairs on both surfaces, turning bronze to dull red before dropping in autumn. Pink flowers open in late spring as or just before the leaves expand, carried in clusters of 5-9. Each flower is about 1.5 inches (4 cm) across with a slender, glandular-hairy tube and protruding stamens, and carries a clove fragrance. Bloom lasts about 2 weeks. Dry capsules follow, 0.5 inch (1.3 cm) long, splitting to release small seed. Growth is slow to moderate, adding 6-12 inches (15-30 cm) per year on established plants. Shallow, fibrous roots make the shrub sensitive to drought, and foliage may scorch on exposed sites with afternoon sun. Powdery mildew can develop on leaves in late summer in humid regions.
Native Range
Native to eastern North America from Quebec and Maine south through the Appalachian Mountains to Virginia, and west to Missouri, Arkansas, and eastern Oklahoma. Grows in dry to moist woodlands, rocky slopes, and clearings on acidic soils at elevations up to 4,000 feet (1,200 m).Suggested Uses
Planted in woodland gardens and shrub borders on acidic soils, spaced 4-6 feet (1.2-1.8 m) apart. Suited to naturalized plantings at woodland edges. The clove fragrance is detectable near walkways and seating areas during bloom.How to Identify
Appearance
Size & Dimensions
Height4' - 8'
Width/Spread4' - 8'
Colors
Bloom Information
Flowers open from May to June, beginning earlier in the southern range and later at higher elevations. Bloom lasts about 2 weeks on a given plant. Flowers appear as the leaves emerge, so foliage partly screens the cluster by the end of the bloom period.
Detailed Descriptions
Foliage Description
Blue-green, turning bronze to dull red in fallGrowing 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 acidic soil with a pH of 4.5-6.0 in part shade with shelter from afternoon sun. Water weekly during the first two growing seasons; established shrubs need supplemental water during dry spells because the shallow root system dries quickly. Maintain a 2-3 inch (5-8 cm) mulch layer to keep roots cool and moist. Powdery mildew develops on foliage in humid late-summer conditions but does not affect long-term health. Lace bugs and spider mites feed on leaves in hot, dry, exposed sites. In wet, poorly drained soils, root rot can occur.Pruning
Prune immediately after flowering, since flower buds for the next year form during summer. Cut dead or crossing stems back to the base to maintain the open form. Older shrubs can be renewed by cutting one-third of the oldest stems to ground level over three years.Pruning Schedule
Prune: June–July
late springsummer
