Physostegia Benth.
Physostegia is a North American genus of 12 species. One species, Physostegia virginiana, is a rather frequent garden plant in Europe. According to Whiteley (2000) a second species (Physostegia angustifolia Fernald) is also cultivated in Europe.
Literature:
Cantino P.D. (1982) A monograph of the genus Physostegia (Labiatae). Contr. Gray Herb. 211: 1-105.
Scheen A.-C., Lindqvist C., Fossdal C.G. & Albert V.A. (2008) Molecular phylogenetics of tribe Synandreae, a North American lineage of lamioid mints (Lamiaceae). Cladistics 24: 299-314.
Whiteley A.C. (2000) Physostegia. In: Cullen J. & al. (eds.), The European Garden Flora, vol. 6. Cambridge University Press, Cambridge: 199.
Taxonomic name: