Indigofera tinctoria

Herbs or subshrubs, perennial, pubescent, hairs appressed, silvery, young growth and flowering parts covered with brownish hairs, becoming glabrate. Stems erect or ascending, much branched, 5–20 dm. Leaves 3–10 cm; stipules caducous, subulate, 1–2 mm; petiole 0.4–1.2 cm; stipels 1–1.5 mm; petiolules 1–1.5 mm; leaflets 7–15, opposite, blades broadly oblanceolate to obovate or elliptic, 10–25 × 3–10 mm, base cuneate, apex broadly rounded or truncate, slightly apiculate, surfaces pubescent abaxially, glabrous adaxially. Peduncles 0.1–0.5 cm. Racemes 5–25-flowered, dense, 0.5–4.5 cm. Pedicels 1–2 mm. Flowers 5–6 mm; calyx 1.5 mm, lobes triangular; corolla pink or salmon pink. Legumes red-brown or dark brown, spreading or reflexed, cylindric, straight or slightly curved or abruptly upturned distally, 20–35 mm, thinly leathery, strigose. Seeds 6–12, greenish to dark brown, cuboid-ellipsoidal. 2n = 16.

Phenology: Flowering year-round.
Habitat: Ruderal areas, disturbed pinelands, hammocks.
Elevation: 0–200 m.

Introduced; Ala., Fla., N.C., S.C., Tenn., s Asia (India), introduced also in Mexico (Tabasco), West Indies (Bahamas, Cayman Islands, Cuba, Hispaniola, Jamaica, Lesser Antilles, Puerto Rico, Virgin Islands), Central America, South America (Argentina, Venezuela), elsewhere in Asia, Africa, Australia.

Discussion

Indigofera tinctoria was an early source of a blue fabric dye (J. A. Duke 1981). It was widely cultivated in tropical areas around the world, and it has naturalized in many regions. Use of the plant as a dye source waned after introduction of a synthetic dye.

Selected References

None.

Lower Taxa