Spiraea densiflora (S. splendens var. splendens)
Habit: once established grows rapidly as a medium sized upright shrub having many branches that can form thickets. Stems are reddish brown with oval to oblong bright green leaves having coarsely toothed margins near the tip of the leaf. Small, clustered flowers at the top of the stems are pink to red forming a corymb (a flat-topped flower cluster) and appearing to be fuzzy due to the long stamens. Subalpine spirea blooms all summer followed by a four celled fruit follicle. Leaves have autumn color.
Ecology: found at elevations between 2000-11,000 ft (600-3400 m) along streams, lakes, in moist rocky areas, or open subalpine forests, from Central California north into Canada and extending east into Central Montana.
Growing Conditions: full sun to partial shade, moist well-drained soil.
1-5 ft (0.3-1.5 m)
2.5-3.5 ft (0.7-1 m)