Plant Lore: Baptisia australis

Ask Google what the most popular color in the world is and blue will win with flying colors – and how appropriate given it's long association with first place, royalty, premier businesses (blue chip) and the like. In the garden, true blue flowers are both coveted and hard to come by, but one of the finest examples come from North America's very own Baptisia australis, known colloquially as false indigo. Each spring, this prairie-loving member of the pea family jumps up to 3'-4' high with deep blue racemes of flowers blossoming from late spring into early summer.

Baptisia australis is a showy perennial in the late-spring garden. Image courtesy Mt. Cuba Center.

Rather than form, it's baptisias function that has lead to it's unique name. Derived from the Greek word "bapto," meaning to dye or to dip (hence, baptism), baptisia has been used as a substitute for true indigo (Indigofera tinctoria) for fabric dye. While it's flowers contain the most obvious blue pigmentation, it's actually the stems and foliage of baptisia that are used to render the dye from (just as with true indigo).

Baptisia australis is a favorite perennial in many designs – even rooftop gardens like this one (when space allows). Image courtesy Staghorn NYC.

Try plantings these tough perennials in the middle-to-back of a sunny border for a bright blue late-spring floral display and clean, voluminous foliage for the rest of the summer.