Campanula americana Tall Bellflower
Campanula americana, Tall Bellflower or American Bellflower, reaches from three to five feet in height, its blue-violet blooms providing a bright late-summer accent to savanna or woodland plantings.
Self-seeding, it is either annual or biennial by habit, seemingly depending on when germination occurs. First-year plants are tight rosettes of heart-shaped leaves (shown below) that shoot up the following spring to form tall stems. Because Campanula americana is the only bellflower with wide-spread petals, a petal tube that elongates with age and stamens that extend over the petals, it often is assigned the special designation Campanulastrum americanum.
Light: Full shade to partial shade
Bloom Color: Blue
Bloom Time: July to October
Foliage Height: 5 feet