Aaron's Beard earns its place through persistence. Spreading by underground stolons, this low evergreen mat colonizes the ground beneath dense tree canopy and on punishing sandy slopes where little else will commit. The powder-puff flowers — bright yellow with hundreds of erect stamens — arrive in summer and are surprisingly showy for a plant doing such utilitarian work.

Growing 1 to 1.5 feet tall, it tolerates heavy clay, dry soil, and deep shade, though it blooms most freely in sun. In colder zones it dies to the ground each winter, but it reliably returns from the roots and flowers on new growth. Cut it back hard in early spring to keep it tidy. Its one genuine vice is vigor: give it room, and keep it away from delicate companions it might overwhelm.