Very floriferous, Campanula medium(Canterbury Bells) is an upright annial with a profusion of large, broadly bell-shaped, blue 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. Canterbury bells are easy to plant and care for. They grow best in full sunlight in moist soil, and cool climates and nutrient-rich fertilizer will ensure a healthy bloom. As a biennial, Canterbury bells take two years to bloom, after which they will die, so many gardeners choose to plant new seeds yearly.