Blue False Indigo (Baptisia australis)

Common Names: False Indigo, Wild Indigo, Rattleweed, Horse Fly Weed

Blue False Indigo (Baptisia australis) is a flowering, herbaceous perennial native to most of the eastern US and is found everywhere from prairies to meadows to open woods. It’s called Blue False Indigo because it was used as a substitute for True Indigo (Indigofera tinctoria) which was used to make blue dye. It was also used by Native Americans as a treatment for toothaches and nausea, as an eyewash and as a purgative.

Blue False Indigo is a slow grower the first couple of year. The plant develops more underground. After two seasons the blooms put on a much better show. It grows in shrub-sized clumps that can reach 3-4 feet tall and about that wide. Its foliage is blue-green. In the winter, the foliage dies back to the ground and needs to be cut back before spring.

It blooms in mid to late spring with 12″ long spires of blue flowers. The blooms resemble pea like flowers and the overall look of the stems and flowers is similar to lupines. The flowering period is 3-4 weeks long and attracts all kinds of pollinators. The deer tend to not forage on Baptisia.

Blue False Indigo need space to grow so be sure to give it plenty of room. It grows well in most well-drained soils. It doesn’t bloom well in acidic soils (add lime to counter the acidity). It is drought tolerant once established but will need regular watering to get established. Baptisias are in the Pea family (Fabaceae) and are legumes like peas. They will add nitrogen to the soil as they grow.

Plant in full sun to part shade 24-36″ apart. Grows 36-60″ tall and 24-36″ wide.

Blue False Indigo is available in our Quart Premium Native Perennials size category.

Scroll to Top