Amorpha fruticosa L.
Amorpha angustifolia (Pursh) Boynt.
Amorpha bushii Rydb.
Amorpha croceolanata P.W. Watson
Amorpha curtissii Rydb.
Amorpha dewinkeleri Small
Amorpha fruticosa L. var. angustifolia Pursh
Amorpha fruticosa L. var. croceolanata (P.W. Watson) P.W. Watson ex Mouillef.
Amorpha fruticosa L. var. emarginata Pursh
Amorpha fruticosa L. var. occidentalis (Abrams) Kearney & Peebles
Amorpha fruticosa L. var. oblongifolia Palmer
Amorpha fruticosa L. var. tennesseensis (Shuttlw. ex Kunze) Palmer
Amorpha occidentalis Abrams
Amorpha occidentalis Abrams var. arizonica (Rydb.) Palmer
Amorpha occidentalis Abrams var. emarginata (Pursh) Palmer
Amorpha tennesseensis Shuttlw. ex Kunze
Amorpha virgata Small
False indigo, desert false indigo, bastard indigobush
False indigo is native through much of North America, and is also naturalized in Europe and Asia. It prefers moist woods and stream banks.
Plants: Shrubs are deciduous, up to 16-20' (5-6 m) in height and 33-39' (10-12 m) around. Lower stems are woody.
Leaves: Leaves are pinnately compound, with 8-35 leaflets per group. The stems supporting the leaflets are light grayish green, with fine hairs. Leaflets are green above, velvety below, ½-1½" (1.3-3.8 cm) × ½-1" (1.3-2.5 cm), generally oblong in shape. The leaf margins are often nearly parellel, rounding abruptly at the ends. Leaflet undersides have scattered, dark, irregularly shaped glands.
Flowers: Flowers appear in narrow, conical racemes 3-6" (7.6-15 cm) long, in groups of 1 to 6. Each flower is ¼" (6.3 mm), tubular, purple to dark blue, with yellow stamens and bright orange-yellow anthers. They appear from April-June.
Fruits: Dense groups of small fruits resembling tiny cucumbers, each up to ⅜" (9.5 mm) long, yellow green, browning with age. Blisterlike glands are visible under magnification. Each fruit has a sharp tip and contains 1-2 seeds.
Amorpha fruticosa at Illinois Wildflowers
Amorpha fruticosa on www.carolinanature.com (Great photos)
Amorpha fruticosa at the Lady Bird Johnson Wildflower Center
Amorpha fruticosa at the Missouri Botanical Garden
Amorpha fruticosa at the Virginia Tech Department of Forest Resources and Environmental Conservation
Amorpha fruticosa on SEINet—the Southwest Environmental Information Network
Amorpha fruticosa description by Thomas H. Kent, last updated 25 May 2020.
Range: Zones 4-9: