Wild Indigo, Baptisia spp, is a lesser talked about and used immune stimulant. The root and/or whole plant, were often paired with Echinacea for stubborn infections. The plant is found in prairie bioregions in both full sun and shade
Here is what Michael wrote about how to use the plant from his Herbal Tinctures in Clinical Practice and Materia Medica Handbook
BAPTISIA (Wild Indigo Root) Full FOLIO HERE
Indications: Any skin or mucoepithelial infections especially from endogenous bacteria, with immunologic depression and poor, asthenic vital functions; adjunct therapy to antibiotics for mild septicemia.
ROOT. Tincture [1:5, 65% alcohol], WHOLE PLANT. Fresh Tincture [1:2], both taken 10-25 drops, to 3X a day, or every three hours initially.
CONTRA: Pregnancy, major pathologies in general, and can stimulate the rate of liver breakdown of some drug therapeutics.
United Plant Savers Lists the plant with an at-risk score of 42. Learn More at their site
If you consider growing it, it likes well drained sandier soils and can thrive in warm, dry sunny or shady locations.