Creeping perennial from the Lamiaceae family, native to Europe and much of the temperate Palearctic, common in cool woodlands, wet meadows, and shaded edges.
It spreads by creeping stolons that root at each node, quickly forming a dense mat. The basal leaves are oval, slightly crenate, medium green in the type species, often tinged with reddish-brown in bright conditions. The upright spikes of 10-20 cm bear blue-violet bilabiate flowers in April-May, highly appreciated by early bees. The species tolerates shade, cool to cool-moist soils, and withstands moderate trampling.
Many cultivars have been selected from this species, mainly for the diversity and ornamentation of the foliage. 'Atropurpurea' is one of the most classic and widespread: its evergreen foliage is a dark, uniform purple-brown with bronze reflections, more intense in full light. The floral spikes reach 15-20 cm. A vigorous and reliable ground cover, often used in contrast with green or silver foliage.