Chinese Indigo

Perennial, Shrubs, Taproot present, Nodules present, Stems erect or ascending, Stems less than 1 m tall, Stems solid, Stems or young twigs glabrous or sparsely glabrate, Stems with 2-branched hairs, dolabriform, Leaves alternate, Leaves petiolate, Stipules inconspicuous, absent, or caducous, Stipules free, Leaves compound, Leaves odd pinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 5-9, Leaves glabrous or nearly so, Inflorescences racemes, Inflorescences spikes or spike-like, Inflorescence axillary, Inflorescence or flowers lax, declined or pendulous, Bracts very small, absent or caducous, Flowers zygomorphic, Calyx 5-lobed, Calyx glabrous, Petals separate, Corolla papilionaceous, Petals clawed, Petals pinkish to rose, Banner petal ovoid or obovate, Wing petal s narrow, oblanceolate to oblong, Wing petals auriculate, Wing tips obtuse or rounded, Keel petals auriculate, spurred, or gibbous, Keel abruptly curved, or spirally coiled, Keel tips obtuse or rounded, not beaked, Stamens 9-10, Stamens diadelphous, 9 united, 1 free, Filaments glabrous, Style terete, Fruit a legume, Fruit unilocular, Fruit freely dehiscent, Fruit elongate, straight, Fruit oblong or ellipsoidal, Fruit coriaceous or becoming woody, Fruit exserted from calyx, Fruit inflated or turgid, Fruit internally septate between the seeds, Fruit glabrous or glabrate, Fruit 3-10 seeded, Seeds ovoid to rounded in outline, Seed surface smooth, Seeds olive, brown, or black.

Indigofera decora, commonly known as summer wisteria, is a species of shrub native to China and Japan that has since been introduced to Australia and Sri Lanka. A member of the genus Indigofera, its family is Fabaceae and is used primarily for decorative purposes, though it has also been used to make indigo-colored dye.

I. decora is a deciduous, spreading shrub. It often grows 1–2.5 feet tall and 3-4 feet wide. It features compound, pinnate leaves up to 8 inches long with 7-13 elliptic, dark green leaflets. In the summer, it produces axillary racemes of light pink or purple pea-like flowers. Each raceme may boast twenty to forty flowers, and the calyxes have broadly triangular lobes.

I. decora is best suited to well-drained, neutral to slightly alkaline soils. It is somewhat heat and drought tolerant, but benefits from afternoon shade in hot, humid environments. It is cold hardy in the US in zones 7–11.