Subalpine spiraea is an attractive, low growing shrub suitable for use in the woodland garden. Its spreading or erect branches are freely branched, and the shrub ranges from 50-100 cm high. The bark is an attractive reddish- or purplish-brown. The stems may be smooth surfaced or thickly haired The lower leaf surfaces and the inflorescence are likewise hairy. The leaves are pinnately simple, and they are alternate on the stems. They are ovate-oval or oblong-elliptic, and range from 2-4 cm long. The upper surface is bright green while the lower surfaces are lighter and strongly veined. The blades are finely toothed for at least half their length.
The inflorescence is a nearly flat-topped or rounded corymb from 2-4 cm wide. The flowers are tiny, with 5 pinkish petals. The petals are oval to narrowly obovate, and range from 1.5-2 mm long.
Subalpine spiraea is found from 2000'-11,000' in mountainous regions. It is usually found along streams, lakes, in montane meadows, or in wooded or rocky slopes.
Subalpine spiraea is found from British Columbia south through the Cascade Mts. and Olympic Mts. to northwestern and Sierran California. It is found eastward to southeastern British Columbia, Montana, Idaho, and eastern Oregon.
