Wild blue indigo

B. australis is an herbaceous perennial that reproduces both sexually and asexually by means of its spreading rhizomes. The plant is erect and emerges from the rhizomatic network. The roots themselves are branched and deep, which helps the plant withstand periods of drought. When dug up they are woody and black in color and show tubercles, wart-like projections found on the roots. The plant branches extensively about halfway up. The stems are stour and glabrous, or hairless. Broken stems secrete a sap that turns dark blue on contact with the air.
The plant may attain a height of 1 to 1.5 meters, and a width of 0.6 to 1 meter. The grey-green trifoliate leaves are arranged alternately, and are further divided into clover-like leaflets that are obovate in shape, or wider towards the apex. Flower spikes appear in early summer. Emerging at the pinnacle are short, upright terminal racemes with pea-like flowers that vary in color from light blue to deep violet. The flowers, which bloom from spring to summer depending on the region, are bisexual and are roughly 2.5 cm long (1 inch). The fruit is a bluish black inflated and hardened pod that ranges from 2.5 to 7.5 cm in length (1 to 3 inches) by 1.25 to 2.5 cm (0.5 to 1 inch). They are oblong in shape and are sharply tipped at the apex. At maturity they will contain many loose seeds within. The seeds are yellowish brown, kidney shaped and about 2 mm (0.08 inches) in size.The leaves emerge about one month before flowering and are shed approximately one month after the pods form. Once the seeds are fully mature, the stems turn a silverish grey and break off from the roots. The pods stay attached and are blown with the stems to another location. (information from Wikipedia)