Tradescantia subaspera Ker

Tradescantia subaspera plant

Family - Commelinaceae

Stems - To 1m tall, glabrous or with sparse pubescence at base, herbaceous, erect, typically simple or branching above, with slight to obvious "zig-zag" appearance, from fibrous to slightly thickened roots.

Leaves - Alternate, sheathing at base, linear-lanceolate, entire, ciliate margined, pubescent below, glabrous above, to +20cm long, +/-5cm broad. Blade much broader than sheaths.

Tradescantia subaspera leaves

Inflorescence - Terminal and axillary sessile bracteate clusters of +/-15 flowers. Pedicels +/-2cm long in flower, glandular pilose at apex, recurving in fruit.

Flowers - Petals 3, blue-purple to pale blue, , to 1.5cm long, 1cm broad, glabrous, ovate. Stamens 6, erect. Filaments to 8mm long, purple, with dense purple multicellular pilose pubescence. Anthers yellow, 2mm broad. Ovary superior, white, globose, 1.5mm in diameter, with multicellular pubescence at apex. Style to 4mm long, purple, glabrous. Sepals 3, ovate-lanceolate, 8mm long, 3-4mm broad, cupped, glandular pubescent, spreading, acute, with scarious margins.

Tradescantia subaspera flower

Tradescantia subaspera calyxPedicel and closed calyx.

Flowering - June - September.

Habitat - Low woods, ravines, streambanks, bluffs.

Origin - Native to U.S.

Other info. - This is another species of the familiar genus Tradescantia, commonly called Spiderworts. This is not, however, the most common species found throughout most of the state. That designation belongs to T. ohiensis, which differs from the above species by having longer thinner leaves, typically straight stems, and sepals and pedicels which are glabrous. You can find this species in this same section on this website.
T. subaspera is found mainly in the eastern half of the state and grows in shaded areas of the habitats mentioned above. Our plants belong to variety subaspera. Another variety, var. montana (Shuttlew.) Anders. & Woods., grows in the eastern U.S.. The latter variety has typically straight stems and axillary inflorescences which are on peduncles.

Photographs taken in Big Spring Park, MO., 7-18-03.