Tall Bellflower (Campanula americana) is an upright annual or biennial that is native to moist open woods, moist meadows, streambanks and ditches in shady areas. In biennial mode, it produces in the first year only a low-growing basal rosette of leaves. In the second year, tall flower stems shoot up from the basal rosette to as much as 6 feet tall clad with rough, toothed, lance-shaped to ovate-elliptic green leaves (to 3-6 inches long). Flat, star-shaped, five-lobed, light blue flowers, each with a distinctively curved and recurved style and a pale white ring at the throat, bloom solitary or in clusters at the leaf axils in summer (June-August). The root system consists of a taproot.
Habitats include moist to slightly dry deciduous woodlands, disturbed open woodlands, woodland borders, and thickets. This plant is often found along woodland paths, and it appears to prefer slightly disturbed areas.
Best grown in rich, moist, well-drained soils in part shade. Plants prefer cool summer climates where they will tolerate full sun, but they prefer part shade (particularly afternoon shade) in hot summer. Plants need regular and even moisture. Plants are annual or biennial, but will easily remain in a garden by self-seeding. The point at which the seeds germinate generally determines whether the plant will grow as an annual or as a biennial. For growth as an annual, start plant seed indoors about 6-8 weeks prior to last spring frost date. For growth as a biennial, plant seed outdoors in the garden in late spring for bloom the following year.