Sp. Pl. 1: 148. 1753 ,.
Plants perennial. Stems erect or ascending, 1–5 (–7) dm. Leaves opposite (whorled); blade linear-lanceolate to lanceolate or elliptic, 8–15 (–20) × 2–6 mm. Pedicels ascending in fruit, 20–50 mm, longer than subtending leaf. Flowers: sepals 5, calyx divided to ca. 1/2, 4–6 mm, shorter than corolla, margins entire, narrowly scarious, apex acute to acuminate; petals 5, corolla blue or red, salverform (almost rotate) to slightly campanulate, 5–12 mm. Capsules 5–7 mm. Seeds 20–45.2n = 22 (Europe).
Phenology: Flowering spring–fall.
Habitat: Coastal sage scrub or dune swales
Elevation: 0-700 m
Introduced; Calif., Va., sw Europe, nw Africa
"dm" is not declared as a valid unit of measurement for this property.