Indigofera is a genus of about 750 species of flowering plants. It may be best known for the tropical herbs Indigofera tinctura and Indigofera suffructicosa, which are both used to produce indigo dye. Other species include annuals, perennials, shrubs and trees, which vary in hardiness from USDA zones 6 to 11.
Indigofera kirilowii grows in in my own garden. Visitors frequently admire the soft, fernlike foliage and want to know about it. Hardy in zones 6 to 9, it is a deciduous, suckering subshrub that has small pinnate leaves and pink and white racemes of flowers from May to midsummer, with sporadic blooms into fall. Its cotton candy colored flowers are attractive to pollinators. It looks much like a ground hugging wisteria.
It grows well on banks and does a great job of stabilizing the soil on a slope. Individual plants grow to about 2 feet tall and wide. They spread by underground runners, and Indigofera kirilowii makes an excellent ground cover for large areas. It is easy to pull up excess plants, but I would never plant Indigofera kirilowii unless it had room to roam.
Indigofera grows well in light shade to full sun. It is not picky about soil, but it will especially thrive in well-draining, loamy soil. My Indigofera grows in a section of the woodland garden that gets no supplemental water, and it has done well. It has been a very low-maintenance plant. Flowers are produced on new wood, and I do usually cut the dead stems to the ground in late winter to neaten the appearance and to make room for the fresh spring growth.