Species Native to Missouri
Common Name: shellflower
Type: Herbaceous perennial
Family: Plantaginaceae
Native Range: United States
Zone: 5 to 9
Height: 2.00 to 3.00 feet
Spread: 1.00 to 2.00 feet
Bloom Time: July to September
Bloom Description: Rose to lavender
Sun: Full sun to part shade
Water: Medium to wet
Maintenance: Medium
Suggested Use: Naturalize, Rain Garden
Flower: Showy
Tolerate: Erosion, Clay Soil, Wet Soil
Culture
Best grown in organically rich, humusy, moist to wet soils in full sun to part shade. Preference is for dappled sun and consistently moist soil conditions. Appreciates a composted leaf mulch, particularly in full sun areas. Consider pinching back the stem ends in spring to reduce mature plant height, especially when growing plants in strongly shaded areas where they are more likely to need some support. In optimum environments, however, staking is usually not required. Although native to swampy areas, this plant generally succeeds in any rich soil in both sunny and shady conditions with some tolerance for brief periods of dry soil. Will self-seed in moist soils. Propagate by division, cuttings or seed.
Noteworthy Characteristics
Chelone oblique, commonly known as turtlehead, is a stiffly erect, clump-forming perennial that typically grows 2-3’ tall. It is native to moist woods, swampy areas, floodplains, alluvial forests and stream margins in parts of the Midwestern and Eastern U. S. from Minnesota to Virginia south to Mississippi and Florida. Hooded, snapdragon-like, two-lipped flowers (each to 1.5” long) ranging in color from red to pink to deep rose bloom in tight, spike-like terminal racemes from late summer into autumn (late July – September). Each flower has a sparse pale yellow beard inside the lower lip. Flowers purportedly resemble the heads of open-mouthed turtles. Pairs of opposite, coarsely-toothed, lance-shaped, dark green leaves appear in pairs along the stem.
Var. speciosa, commonly called rose turtlehead, is native to the Midwestern U.S. ranging from Minnesota to Indiana south to Kentucky and Arkansas. In Missouri, Steyermark reports that this variety has been rarely encountered in 5 counties where it is typically found growing in swampy meadows, margins of springs in calcareous open meadows, and low or swampy woods in valleys along or near streams. It is noted for producing deep rose to mauve-lavender flowers. Upper bracts of this variety are obtuse rather than narrow and the sepals are ciliolate.
Genus name comes from the Greek word chelone meaning tortoise in reference to the turtlehead shape of the flowers.
Specific epithet means lopsided or oblique.
Problems
No serious insect or disease problems. Some susceptibility to mildew, particularly if soils are kept too dry and/or air circulation is poor. If grown in too much shade, plants may need some support.
Uses
Shade or woodland gardens. Native plant gardens. Bog gardens. Pond or water garden peripheries. Borders as long as the soil moisture requirements can be met.