Perennial or occasionally annual herbs, rarely twining. Leaves alternate, simple, sheathing at base; petiole often present; lamina narrow or expanded, parallel veined. Inflorescence various, basically cymose, several-flowered. Flowers usually bisexual, regular or irregular; sepals 3, usually green, sometimes petaloid and coloured; petals 3, usually blue or white, equal or unequal, often with basal half much narrower than more or less broadly ovate to subcircular distal half; stamens (or sometimes staminodes) in 2 whorls of 3, filaments usually slender, anthers fixed at base or versatile; carpels 3, fused, superior; ovary with 3 chambers, often imperfectly developed, ovules 1–many in each functional chamber of ovary. Fruit usually a loculicidal 2- or 3-chambered capsule; seeds with endosperm.
About 700 species in about 50 genera, common in tropical and subtropical regions; 2 species in Victoria.
Species of Tradescantia (Spiderwort) and Zebrina pendula (Wandering Jew; a vernacular name also used for Tradescantia albiflora) are commonly cultivated.