Canterbury bells plant (Campanula medium) is a popular biennial (perennial in some areas) garden plant reaching about two feet (60 cm.) or slightly more. Campanula Canterbury bells can be easily grown and cared for much like their bellflower counterparts. Growing Canterbury bells in your garden can add grace and elegance. Very floriferous, Canterbury Bells is an upright biennial with a profusion of large, broadly bell-shaped flowers, 2 in. wide (5 cm). Blooming from late spring to mid-summer, the flowers are borne atop long leafy stems above a basal rosette of lance-shaped, dark green leaves. Excellent source of nectar or pollen, they attract honey bees and butterflies. Old-fashioned but lovely, Canterbury Bells are well-suited to perennial borders and cottage gardens. Thrives in full sun or part shade, in fertile,moist,well-drained soils. This plant tolerates a wide range of soil types if well-drained.