Foxglove is a biennial, otherwise known as a perennial with a two-year life expectancy. The leaves are soft, hairy, ovate rosettes that appear the first year. The second year purple, white (sometimes yellow or pink) flowers appear. Propagation is through seeds—self-propagation carries the plant to some unusual locations. Foxglove prefers loamy soils, but is often found in rock wall crevices as well as dry hilly pastures, and along roadsides.
Foxglove contains cardiac glycosides, rendering all parts of the plant poisonous. Ingesting the plant can be fatal to young children and pets. Adverse symptoms include dizziness, irregular heartbeat, delirium, hallucinations and vomiting. Foxglove is a source for digitonin, a digitalis drug used by physicians during heart failure. The therapeutic dose is close to the lethal dose.