Glabrous, often glaucous perennial herb, 10–70(–100) cm high; stems erect, unbranched or branched near base, striate. Leaves linear to linear-elliptic, 5–20 mm long, 1–2(–3) mm wide, acuminate, margins entire. Inflorescences loose terminal corymbose panicles or rarely flowers solitary; pedicels slender, erect, 5–25 mm long, elongating in fruit. Sepals ovate, 3–6 mm long, acute or acuminate, margins white-membranous and ciliolate; petals obovate to obovate-cuneate, 8–15 mm long, blue, rarely white, often veined darker; anthers white; styles united from base for greater than half their length, stigmas linear, decurrent along inner side of style-branches. Capsule 3–6 mm diam., beaked; seeds 2.5–3 mm long, brown. Flowers mostly spring and summer.