Dianthus is a genus of about 300 species of flowering plants in the family Caryophyllaceae, native mainly to Europe and Asia, with a few species extending south to north Africa, and one species (D. repens) in arctic North America. Common names include carnation (D. caryophyllus), pink (D. plumarius and related species) and sweet william (D. barbatus). The species are mostly herbaceous perennials, a few are annual or biennial, and some are low subshrubs with woody basal stems. The leaves are opposite, simple, mostly linear and often strongly glaucous grey-green to blue-green. The flowers have five petals, typically with a frilled or pinked margin, and are (in almost all species) pale to dark pink. One species, D. knappii, has yellow flowers with a purple centre. Some species, particularly the perennial pinks, are noted for their strong spicy fragrance.