Prunella is a small genus of herbaceous perennial plants in the mint family Lamiaceae, order Lamiales. Commonly known as self-heals, heal-all, or allheal — names that reflect a long history of use in folk and herbal medicine — the genus comprises roughly a dozen species plus several naturally occurring hybrids.
Plants in the genus are low-growing and mat-forming, with the square stems characteristic of the mint family. They thrive in moist, disturbed ground: grassland, woodland edges, roadsides, and lawns. Leaves are opposite and typically ovate; flowers are two-lipped (bilabiate) and borne in dense terminal spikes, usually violet to purple, occasionally white or pink.
The genus is centered on Europe, Asia, and North Africa, with most species restricted to the Mediterranean basin or specific mountain ranges. The most widespread member, Prunella vulgaris (common self-heal), is Holarctic in distribution, occurring throughout Europe, Asia, North Africa, and North America, and has become naturalized in New Zealand and parts of South America. Several species in the genus are naturally occurring hybrids, including P. × bicolor, P. × intermedia, and P. × surrecta.
Prunella has been used medicinally by diverse cultures: indigenous peoples of the Pacific Northwest applied the juice to boils and used the whole plant on cuts and inflammations, while in Chinese herbal medicine dried Prunella (夏枯草, xià kū cǎo) is prepared as an herbal drink and used for conditions including halitosis.
Etymology
The common names self-heal, heal-all, and allheal all refer to the traditional use of Prunella species in herbal medicine to treat a range of minor ailments. The genus name Prunella is of uncertain origin; it has been linked to the German word Bräune (quinsy, a throat inflammation), reflecting early medicinal associations.
Distribution
Most Prunella species are native to Europe, Asia, and North Africa, with the genus concentrated in the Mediterranean region and mountain ranges of western Eurasia. Prunella vulgaris is the exception: it is Holarctic in distribution, occurring across Europe, Asia, North Africa, and North America, and has been naturalized in New Zealand and parts of South America, where it is often encountered as a lawn weed.
Ecology
Prunella species are low-growing ground-cover plants that spread rapidly in moist, disturbed habitats — wasteland, grassland, woodland margins, and lawns. Prunella vulgaris in particular is a common lawn weed throughout its wide range. The square stems and opposite leaves are typical of the mint family (Lamiaceae), and the dense flower spikes attract pollinators.
Cultural Uses
Prunella has a broad ethnobotanical record. In the Pacific Northwest, the Quinault and Quileute peoples used the plant's juice on boils and applied the whole plant to cuts and inflammations, sometimes fixing it with grease to make an ointment. In Chinese herbal medicine, dried Prunella — known as 夏枯草 (xià kū cǎo, "summer dried herb") — is brewed as a herbal drink; it is also used for halitosis, often combined with perilla, field mint, or other herbs.
