Species Native to Missouri
Common Name: tall bellflower
Type: Herbaceous perennial
Family: Campanulaceae
Native Range: North America
Zone: 4 to 7
Height: 3.00 to 6.00 feet
Spread: 1.00 to 2.00 feet
Bloom Time: June to August
Bloom Description: Blue
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Annual, Naturalize
Flower: Showy
Culture
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 climates including Missouri. Plants need regular and even moisture. Deadhead spent flowers to encourage additional bloom. 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.
Noteworthy Characteristics
Campanula americana, commonly called tall bellflower, is an upright annual or biennial that is native to moist open woods, moist meadows, streambanks and ditches in shady areas of eastern North America from New York and southern Ontario to Minnesota south to Florida, Alabama, Arkansas and Oklahoma. In Missouri, it is commonly found in every county throughout the State. 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' tall clad with rough, toothed, lance-shaped to ovate-elliptic green leaves (to 3-6" long). Flat, star-shaped, five-lobed, light blue flowers (to 1" across), 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).
Plants in the genus Campanula usually have bell-shaped flowers (from Latin campana meaning little bell). Tall bellflower is one of the exceptions, however, in that it has flattened rather than bell-shaped flowers. These flower differences have in large part resulted in the recent reassignment of this plant by some authorities into a separate genus under the name of Campanulastrum americana.
Genus name comes from the Latin campana meaning bell in reference to the bell-shaped flowers.
Specific epithet means form America, North or South.
Problems
No serious insect or disease problems. Slugs and snails are occasional visitors. Watch for aphids.
Uses
Moist shaded areas of rock gardens. Also effective in lightly shaded woodland areas where plants can be left alone to naturalize. Mass or large groups are best.