Tall bellflower is an abundant native bellflower that is easily identified by its stout, tall habit, short, wheel-shaped, blue corolla, and the curved, purple style that projects beyond the flower.
Tall bellflower is a robust annual or biennial with a straight stalk, unbranched or sparsely branched near the top, that often persists in winter. The sap is milky.
The flowers are tubular with 5 large, spreading lobes; saucer-shaped (not bell-shaped); arising singly or in clusters of 3 on a very long spike. The flowers are light blue to (rarely) white and have a white ring at center. The style is curved, purple, and projects well beyond the flower. The flowers often open without any apparent sequence along the stalk.
Blooms July–September.
The leaves are alternate, 3–6 inches long, lance-shaped, and sessile or with very short stems.
Similar species: Missouri has 4 species in the genus Campanula. Two of them are fairly uncommon natives, and one is an aggressive nonnative:
- Marsh bellflower (Campanula aparinoides) is a Missouri native that lives in fens and calcareous swamps. Its 5-lobed flowers are pale blue to nearly white, its leaves are narrow, and its slender stems spread loosely and often recline on other plants. The stems and leaves are roughened with short hairs that curve backward.
- Harebell, or bluebell (Campanula rotundifolia), is known in Missouri from only one location along the Jacks Fork River in Shannon County. That small population may be a glacial relict that has survived in extra cool, moist locations ever since the last glaciers retreated from our region. Its flowers are violet blue, bell-shaped with 5 pointed lobes, and in loose clusters of 3 to 8 nodding flowers.
- Creeping bellflower (Campanula rapunculoides) is an introduced Eurasian plant that can spread aggressively via creeping rhizomes and can be hard to eradicate once established. Also called rover bellflower or false rampion, it has a longer, bell-shaped corolla, and the style is straight and only slightly protruded (exserted) from the corolla. The leaves are lanceolate. It is scattered mostly in the northwestern quarter of Missouri.
Height: to 6 feet.
Abundant statewide.
Habitat and Conservation
Occurs in forest edges, open, moist woodlands, bluffs, disturbed areas, and roadsides. This species is widespread in eastern North America.
Status
Native Missouri wildflower.
Human Connections
This plant is an easy garden subject, spreading by seed. Although each flower is open for only a short time, the plants keep producing new blooms.
Whether it has been cultivated in a garden or blooms along trailsides "for free," this showy native wildflower pleases the eye.
If the genus name, Campanula (kam-PAN-you-luh), sounds slightly familiar, you may have studied architecture, or you may be a pasta aficionado. The Italian word for "bell tower" is campanile (KAM-puh-NEE-lay), and the term for pasta in the shape of little bells is campanelle (KAM-puh-NELL-ay).
Ecosystem Connections
Bumblebees, megachilid bees, and other long-tongued bees are the primary pollinators of this species, though other bees, butterflies, and hummingbirds visit the flowers, seeking nectar, pollen, or both.
The pollination strategy of tall bellflower is remarkable: the flowers can develop in a way that allows them to self-fertilize, or they can develop in a way that encourages them to cross-pollinate with other flowers, depending on how many pollinators are present.
In the cross-pollination strategy, a tall bellflower's pollen matures and is dispersed by insects before its stigma has matured and is capable of receiving pollen. The stigma only becomes mature when it elongates and forms its S-shaped curve; at this point, insects deliver pollen from other flowers to it.
Deer reportedly eat this plant.
Genus Campanula is the namesake for its family, the Campanulaceae (kam-pan-you-LAY-cee-ee). Other members of the bellflower family include lobelias, balloon flowers, and several additional kinds of bellflowers, which are popular with gardeners. Our native red and blue cardinal flowers and Venus' looking glass are also members of the family.
The genus name, Campanula, means "little bell," and most members of the famous bellflower genus have bell-shaped (campanulate) flowers. American bellflower, however, is an oddball for its genus, since it has saucer-shaped flowers.
Because tall bellflower is apparently not closely related to the other members of its genus, some botanists have given it its own genus, "Campanulastrum." Some references therefore call it "Campanulastrum americanum." However, critical characteristics often used to segregate it (such as the saucer-shaped, not bell-shaped corolla) are indeed found in other species of Campanula, so most botanists retain it in that genus.
