Creeping St. John's Wort Aaron's Beard

Creeping St. John's wort (Hypericum calycinum, Hypericaceae) is a semi-evergreen, stoloniferous subshrub from southeastern Europe and Asia Minor, reaching 12 to 18 inches tall (occasionally 3 feet) with a spread of 24 inches or more. Large yellow, five-petaled, rose-like flowers (5 to 8 centimeters) with bushy reddish-anthered stamens bloom in early summer and sometimes through the season.

Creeping St. John's wort grows in sun to shade on adaptable, well-drained soils, hardy in Zones 6a to 8b. It tolerates drought, erosion, and dry soil. Documented diseases include root rot and rust. The species can be invasive in some regions via creeping rhizomes, above-ground stems, and seed dispersal. No cultivars are documented.