Alpine Aster
Aster alpinus
A cushion-forming perennial of the Alberta high country — found on rocky alpine slopes in the Rockies and Foothills, where it puts out solitary lavender-purple daisies on short stems above tight rosettes of greyish leaves from late June into August. One of the few true Aster (rather than Symphyotrichum) species native to North America, and a star of rock gardens for its early bloom and tidy 15–25 cm height. Tolerates wind, cold, and lean gravelly soil that defeats most border perennials.
Quick Facts
Distribution
Rocky Mountains, Foothills (alpine & subalpine), Zone 2
Light
Full sun
Bloom Time
Late June–Aug
Soil
Sharply drained gravel, scree, or sandy loam; neutral to slightly alkaline; rots in heavy or wet soils
Water
Low; drought-tolerant once established
Growing & Cultivation
Best Planting Time
Fall (preferred) or early spring
Propagation
Seed sown in fall (natural cold stratification) or after 30 days cold-moist stratification in spring. Also by careful division of mature clumps in early spring or after flowering.
Spacing
20–30 cm
