Amorpha fruticosa

Common Names

False Indigo-Bush, Bastard-Indigo

Summary

Amorpha fruticosa, commonly called False Indigo, is a deciduous nitrogen-fixing shrub native to most of the contiguous United States and extending into northern Mexico. It grows as a multi-stem, spreading shrub reaching roughly 4–12 feet tall with a dense thicket-forming habit, and bears pinnately compound leaves with 11–25 leaflets. Dense spikes of purple flowers with orange anthers appear on the plant, followed by brown legume fruits; bluish-green foliage provides a fine-textured backdrop. Cultivation favors full sun to partial shade with well-drained soils; tolerant of drought and adaptable to poor, sandy, loamy, or even wet soils, though drainage matters. Propagation by seed (often scarified) or cuttings; seeds may require scarification and germination periods vary. Spreads by seeds and suckers to form dense thickets; used for erosion control, windbreaks, shelterbelts, and wildlife habitat; attracts bees and butterflies, and serves as a nitrogen-fixing contributor to nearby plants. Pruning in late winter to early spring helps maintain shrub form. Generally pest-free.

Lifecycle

Perennial

Height

48-144 inches

Spread

98-157 inches

Hardiness Zones

Zones 4-9

Sunlight Requirements

Ideally Full Sun. Tolerates Partial Shade.

Soil Type

Light, well-drained sandy soil

Soil Drainage

Well-drained soil, Moist but well-drained soil, Well-draining loamy soil with moisture retention but not waterlogged

Soil pH

Tolerates all pH levels

Bloom Color

Blue to purple (deep purple or blue); some cultivars have white or pale blue flowers

Bloom Time

Spring to Summer

Foliage Color

Green

Fall Foliage Color

Gold/Yellow, Reddish-gold tints

Leaf Lifecycle

Deciduous

Growth Rate

Fast-growing

Seasons of Interest

Spring, Summer, Fall, Winter

Propagation Methods

Seeds, Cuttings, Layering, Suckers

Attracts Wildlife

Attracts bees, butterflies, other pollinators, and birds