False Indigo Type: Perennials Height: Tall 3' (Plant 3' apart) Bloom Time: Early Summer to Summer Sun-Shade: Full Sun to Mostly Sunny Zones: 3-9 Find Your Zone Soil Condition: Normal, Acidic, Sandy Flower Color / Accent: Blue / Blue
False Indigo (Baptisia australis) is a big perennial that's tough as nails, false indigo kicks off summer with spires of pure blue (cultivars come in a variety of other colors). Its rounded form makes a great contrast to the verticality of prairie grasses. False indigo develops deep taproots, so site it in a spot for the long term. It self-seeds modestly, and it's safe to move seedlings when small. Grows up to 4 feet high and wide in Zones 3 to 9.
Baptisia australis (Blue false or wild indigo) A long-time garden favorite, it produces large spires of violet-blue flowers in late spring to early summer on a rounded mound of foliage that remains attractive throughout the season. Hardy in Zones 3-9, it gets 3-4 feet tall and wide.