Cascade Azalea

Rhododendron albiflorum

Native to:
Canada, United States

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Taxonomy

Division:
Magnoliophyta | - Flowering plants
Family:
Ericaceae
Genus:
Rhododendron
Species:
Rhododendron albiflorum
USDA Symbol:
RHAL2

Growth Characteristics

Life Cycle:
Perennial
Growth Habit:
Shrub
Height:
300 cm
Light Requirements:
Full Sun,Part Shade,Shade
Drought Tolerance:
Low
Bloom Months:
jun,jul,aug
Bloom Colors:
white
Landscaping Shrub:
Yes

Wildlife Benefits

Bees:
★☆☆☆☆ Documented bee visitation (GBIF)
Butterflies & Moths:
★★☆☆☆ Documented Lepidoptera association (GBIF)
Caterpillars:
★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)

Keystone Species Ranking

Caterpillar Keystone:
★★★★☆ Butterfly & moth species supported by this genus (NWF)

Host Plant for Caterpillars

Lyonetia candida

Reported Fauna Sightings

Bees: Black-tailed bumble bee (Bombus melanopygus), Fuzzy-horned bumble bee (Bombus mixtus), Sitka bumble bee (Bombus sitkensis)

Garden & Ecology Notes

Wildlife Value:
bees, butterflies, hummingbirds

Soil Requirements

Soil Type:
moist, well-drained, acidic soil
pH:
4.5 - 6.0 (acidic)
Drainage:
excellent drainage required
Moisture:
consistently moist
Notes:
prefers organic-rich soils in forested areas

Propagation & Germination

Stratification:
Cold/moist stratification required — 60–90 days
Germination Time:
30–60 days
Notes:
Seeds require cold stratification for 60-90 days; surface sow on moist peat or sphagnum.

Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).; then Cold-moist stratification for 60 days.

Source: Claude AI

ORGHPS Germination Guide: Sow @ 20°C. Seed germinates within 3 months * sprinkle seed on 10 cm damp sphagnum moss; cover with clear plastic pop bottle cut in half; transplant seedling to acidic mix in shade outdoors when 5 cm high; protect from rodents and give protection in cold frame first winter

Source: Ontario Rock Garden & Hardy Plant Society