Culture
Grow in average, medium moisture, well-drained soil in full sun. Tolerates alkaline soils and some drought. Intolerant of the hot and humid summers of the deep South. Plants may suffer some tip damage or die to the ground in harsh winters, but should come back nicely. As with buddlejas, this plant is often grown in the manner of an herbaceous perennial in USDA Zones 5 and 6A by cutting back all stems close to the ground in late winter to early spring each year before new growth appears. Also often needs a similar hard pruning in warmer climates to maintain good form. Blooms on new growth.
Noteworthy Characteristics
Indigofera kirilowii is a dense, suckering shrub or subshrub which typically grows 2-3' (less frequently to 4') tall. Features dense, axillary racemes (4-5" long) of pink, pea-like flowers which bloom heavily in June and July and sometimes continue intermittently to September. Compound pinnate leaves (each with 7-11 rounded leaflets) are bright green and 4-6" long. A separate species, Indigofera tinctoria, is the species that has been used for many years to produce indigo dyes.
Genus name comes from indigo plus Latin fero meaning to bear. The dye indigo is obtained from this genus.
Problems
No serious insect or disease problems.
Uses
Mixed borders or foundation plantings. Also effective as part of a naturalized planting.