- Perennial forb.
- Prostrate, mat forming, to 1.5 m, rooting at nodes, glabrous.
Stem and node.
- Opposite, simple, entire, petiolate. Petioles 9-18 mm long. Blades 1.5-7.0 cm long, 0.8-5.5 cm wide, ovate to triangular-ovate, narrowed or slightly tapered to a usually sharply pointed tip, broadly rounded to truncate or shallowly cordate at the base, the smallest leaves with blades sometimes appearing angled at the base, the margins densely but inconspicuously pubescent with short, stiff, somewhat appressed-ascending hairs. Blade surfaces glabrous, often mottled with lighter shades of green.
- Solitary axial flowers. Peduncles 16-50 mm long.
- Calyx lobes 9-12 mm, linear, sharply pointed at the tip, glabrous or hairy. Corollas trumpet-shaped, the tube funnelform, 12-20 mm long, blue or bluish lavender, rarely white, hairy on the inner surface near the stamens, the lobes 15-25 mm long, slightly shorter than to longer than the tube, spreading, often somewhat asymmetrical toward the tip. Stamens attached toward the midpoint of the corolla tube, the anthers incurved but free from and positioned above the stigma, narrowly obovate, hairy. Nectar glands 2, positioned on opposite sides of the ovary bases. Style gradually broadened toward the tip, the stigma more or less conical, with a narrow, disclike rim or wing of tissue at the base and minute tufts of hairs at the tip and base.
- Rarely produced. Follicles 2-7 cm long, erect or ascending, relatively stout, narrowed or tapered above and below the seed(s), dehiscing longitudinally only with age. Seeds 1(2-5) per fruit, 3-7 mm long, mostly narrowly elliptic-ovate in outline, flattened, with a deep, longitudinal groove, the surface otherwise finely wrinkled, glabrous, dark brown to nearly black.
- April - May.
- Old homesites and cemeteries, forests.
- Native to Eurasia.
- Since this species rarely produces viable fruits, its presence usually indicates former cultivation. It is less common than its close relative
, which it strongly resembles. The two differ in several somewhat subtle aspects.
has leaves which are rounded rather than tapered at the base, and which have longer petioles (use a large and well-developed leaf for this comparison). The flowers are also larger and the calyx lobes longer and narrower.
The names "vinca" and "periwinkle" have been used indiscriminately to refer to both
spp. and species of
, another genus within the Apocynaceae. This ambiguity can cause confusion and is a good illustration of the importance of using scientific nomenclature when communicating the true identity of a plant.
Photographs taken near Labadie, MO, 4-22-2006 and 4-28-2019 (SRTurner).