Digitalis purpurea (Common Foxglove) Adding a bold, vertical dimension to perennial flower beds, shade gardens, and cottage gardens, Digitalis purpurea (Common Foxglove) is a stately biennial or short-lived perennial boasting tall, one-sided spires of pendant, tubular, bright rosy-purple flowers, 2-3 in. long (5-7 cm), with white speckled throats.