Azalea x 'Delaware Valley White' (Glenn Dale hybrid)

Delaware Valley White Azalea

Azalea × ‘Delaware Valley White’ is a classic evergreen azalea prized for its pure white flowers, excellent cold hardiness, and reliable spring performance. Blooming in mid spring, the clean, bright blossoms often feature a faint greenish throat and provide a crisp contrast to darker evergreen foliage.

The plant develops a dense, low, spreading habit with dark green, glossy evergreen leaves, offering year-round structure and making it especially effective for mass plantings. ‘Delaware Valley White’ is widely regarded as one of the hardiest white-flowering evergreen azaleas for northern landscapes.

Key features


Width: 4–6 ft



Height: 3–4 ft



Flower color: Pure white (occasionally with pale green throat)



Bloom time: Mid spring



Foliage: Dark green, evergreen



Form: Dense, low, spreading



Life cycle: Evergreen shrub



Growing conditions


Sun: Part shade (morning sun, afternoon shade preferred)



Soil: Acidic, moist, well-drained; rich in organic matter



Water: Moderate; consistent moisture preferred



Hardiness: USDA Zones 5b–8b



Landscape use


Foundation plantings



Woodland edges and shade gardens



Evergreen mass plantings



Mixed shrub borders



Notes


Considered one of the best white evergreen azaleas for cold climates



Generally deer resistant



Mulch to keep roots cool and evenly moist



Protect from winter winds in colder sites



Prune immediately after flowering if shaping is needed

Plant type

Evergreen Shrub, Flowering Shrub

Height

3-4'

Width

4-6'

Hardiness zones

5–9

Growth rate

Moderate

Bloom time

Spring

Leaf color

Green

Fall color

Yellow

Soil

Well Drained

Landscape use

Foundation, Mass Planting

Shape

Oval/Rounded

Deer resistant

Yes

Drought tolerant

No