They are borne in thick, spires in mid-summer. Although this plant is a perennial, it is short-lived and best treated as a biennial. D. mertonensis is a very attractive variety that forms basal rosettes of dark green, lance-shaped leaves. They are produced in long, erect spikes from late spring to early summer. They are pale yellow with brown veins.
Foxgloves grow best in moist, moderately fertile soil that is well drained.
They should be in a spot withmottled sunshine, but they will tolerate sun. D. mertonensis will tolerate dry soil. D. ferruginea should be increased by sowing seeds in the fall. D. grandiflora and D. mertonensis can be increased by sowing seed in the spring and the latter can also be propagated by division after it has bloomed. Any of several herbs of the genus Digitalis, especially D. purpurea of Europe, having a long cluster of large, tubular, pinkish-purple flowers and leaves that are the source of the drug digitalis.