Prairie Alum Root

Heuchera richardsonii

Saxifragaceae (saxifrages)


Flowers on tall, hairy, leafless flowering stems (scapes) in open or dense terminal panicles. The flowers are greenish or yellowish green, sometimes tinged with red, small (just under ½ inch long),bell-shaped, the upper lobes longer than and drooping over the lower ones, with orange-tipped stamens slightly emerging from the flower. Blooms April–June. Leaves basal on long, hairy petioles, palmate, often deeply cleft with large teeth; 3–5 lobes, quite showy.

Similar species: There are 4 species of Heuchera in Missouri. Common alum root (H. americana) is absent from the northwest third of the state and parts of the Bootheel; it has smaller flowers and is common on bluffs and rocky woods. Small-flowered alum root (H. parviflora) grows on bluffs and rock outcrops in the Ozarks.; its leaves have rounded lobes. Maple-leaved alum root (H. villosa) is uncommon and known only from Shannon County.


Height: to 10 to 40 inches (flowering stalk); leaf clump to 18 inches high.

Habitat and conservation

Occurs in upland prairies, glades, ledges and tops of bluffs; rock outcrops in moist to dry upland forests; also roadsides and railroads in sunny situations.

image of Prairie Alum Root distribution map
Distribution in Missouri

Scattered nearly statewide; most abundant in Glaciated and Unglaciated Plains sections; apparently absent from the Southeast Lowlands.

Human connections

Alum roots have a long history of various medicinal uses. A close relative, coralbells (H. sanguinea), a red-flowered native of the southwestern U.S. and Mexico, is familiar to gardeners and has many cultivars available. Our native alum roots are often cultivated as ornamentals, too.

Ecosystem connections

Small bees, and no doubt other small insects, visit the flowers. Prairie plants that bloom any time besides early spring typically put their blossoms high atop tall flowering stalks. During their blooming time, they therefore keep above the grasses that eventually grow taller.