Culture
Grow in average, medium moisture, well-drained soil in full sun. Tolerates alkaline soils and some drought. Plants are intolerant of the hot and humid summers of the deep South where some part afternoon shade may help prevent leaves from bleaching. Plants may suffer some tip damage or die to the ground in harsh winters of USDA zone 5, but should come back nicely in spring. Flowers bloom on new growth. Several pruning options exist. As is often done with Buddleja, plant stems may be cut back close to the ground in late winter to early spring each year before new growth appears. Another option is to simply prune stems back to live wood in early spring of each year. Plants will sucker to form large colonies in optimum growing conditions. Promptly remove suckers to prevent unwanted spread.
Noteworthy Characteristics
Indigofera decora, sometimes commonly called Chinese indigo, is a deciduous, spreading shrub that is native to Japan and China. It typically grows to 1-2 1/2' tall and spreads to 3-4' wide or more. Each compound pinnate leaf (to 8” long) has 7-13 elliptic, dark green leaflets. Dense, axillary racemes (to 4-8” long) of light pink, pea-like flowers (each to 3/4" long) bloom heavily in June and July but sometimes continue blooming intermittently to September. Indigofera tinctoria is a SE Asian 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.
Specific epithet means decorative.
Problems
No serious insect or disease problems.
Uses
Mixed borders or foundation plantings. Effective as a shrubby ground cover for slopes, sunny woodland areas or cottage gardens. Rock gardens.