Schwerin's Indigobush

Size, growth and what to expect

No source rates its growth, so our growth estimator uses the fast rate of our indigobush, about 2.75 feet a year while young. It makes a bushy, widely branched shrub 3 to 10 feet tall. Its leaves run 2 to 8 inches long, with up to 29 small leaflets.

One or two spikes up to 6 inches long top the strongest shoots from April into June. Each small flower has one dark purple petal and ten long golden stamens. The hairy pods, about a quarter inch long and each holding one seed, ripen from June into October.

It grows wild in the Piedmont from central North Carolina to northeastern Alabama, with a few sites in South Carolina and northeastern Mississippi. Its home is dry, rocky oak woods on hills and monadnocks, granite outcrops, river bluffs and, less often, floodplain forests. Quarrying, logging, pine plantations and fire suppression have taken some of its sites.

How to grow Schwerin's Indigobush

Schwerin's indigobush grows in full sun or part shade, in a dry, rocky soil that drains well. In the wild it grows under open oak woods on rocky hills and river bluffs, and it does best where fire or a fallen tree lets in more light. Set plants 5 feet apart and 5 feet from a wall. At its size it can go within 15 feet of overhead wires.

Saplings ship bare-root or potted. Plant them dormant, in a hole wider than the roots and no deeper. Set the crown at the soil line, put the native soil back in, and keep the mulch clear of the stems. Other amorphas have a hard seed coat that a winter outdoors helps to soften. Sow the seed outdoors in fall, about a quarter inch deep.

Water weekly through the first summer, then only in long droughts. Keep taller shrubs and vines from closing in over it, since deep shade holds it back.

Each flower carries both male and female parts, so there are no male and female plants to pair. Bees visit the flowers. Birds open the ripe pods and eat the seeds.