Central Appalachians are familiar with this perennial herb, whose slender, foot-long stems and bright blue flowers are often spied reclining among rocks at higher elevations. This species of Scutellaria has weaker stems and bluer flowers than the other species, which tend to have an erect habit and lavender-blue or whitish blooms. Rock skullcap thrives in shady areas with rough or rocky soils and moist conditions; however, it also appears in drier soils and in open areas with part sun. In Ohio, it tends to grow in semi-shady areas. It’s listed as globally rare because of its restricted range in North America, which extends from Delaware to southern Indiana and south to Georgia. It’s uncommon or rare throughout this range, although it rises to “threatened” status in Ohio. According to the U.S. Forest Service, about 60% of the populations nationwide occurs on protected land. The biggest threats to the species are soil disturbance from logging--which increases erosion--and competition from invasive, non-native plants.
The genus Scutellaria belongs to the Mint family, as evidenced by the four-sided stems. Scutellaria species have distinctive protuberances on the upper lip of the flower’s corolla. The Latin word scutella means a small dish or saucer, referring to the helmet or skull-like shape of the calyx protruding over the base of the flower. The nutlets of rock skullcap lack hairs, which may be an inspiration for another common name, smooth rock skullcap. The plant is mostly deer and rabbit resistant because the leaves have a bitter flavor. It spreads by rhizomes and seeds and has no serious disease or pest issues.
Native habitats include rocky forests; cliffs; high elevations; sides of roads; and dry, rocky slopes. Ideal for partly shady rock gardens and areas with non-aggressive plants.
Plant Characteristics:
Grows up to 18” tall.
Prefers part to full shade.
Prefers average to rich soils in damp to dry conditions.
Blue to violet-blue flowers appear early July-September, followed by 2-part capsules containing nutlets July-October. Terminal, 2-3” racemes contain one or several two-lipped flowers.
Scalloped-edged, triangular- to ovate-shaped, green leaves are about an inch long with 1” petioles (leaf stalks). They are spaced in pairs along the stem, which may be waxy or covered with curved hairs.
Wildlife Value:
Host plant for larvae of some moth species, including skullcap skeletonizer moth. Bees and butterflies visit the flowers. Deer avoid browsing the bitter leaves.
Medicinal, Edible, and Other Uses:
Some species of skullcap in North America and China are used to prevent or treat various disorders, including anxiety, Parkinson’s, and Alzheimer’s disease.
Skullcap, Rock, Scutellaria saxatilis Riddell
Once we're certain we have good germination, we'll make these plants available for prepurchase.