Baptisia (false indigo)

Baptisia australis (blue false indigo, incl. dwarf var. minor) and hybrids such as 'Purple Smoke', the Prairieblues and Decadence series; white false indigo (B. alba) and yellow B. sphaerocarpa are close kin used in many hybrids · Pea family (Fabaceae)

At a glance
Hardiness zones	3 to 9
Sun	full sun
Water	low
Life cycle	perennial
Frost	Hardy: takes frost

About Baptisia (false indigo)

Baptisia is a long-lived native perennial that grows into a shrub-sized clump of blue-green, clover-like leaves, with foot-long spikes of indigo-blue pea flowers in late spring and puffy pods that ripen black and rattle (Wisconsin Extension, NC State). Blue false indigo is native from Pennsylvania to southern Indiana and south to Georgia and Tennessee, with a smaller form (var. minor) from Iowa and southeast Nebraska to Texas (Wildflower Center); it was Perennial Plant of the Year in 2010. It's tough, drought tolerant and seldom touched by deer, but all parts are mildly poisonous if eaten.

Blue false indigo is hardy in zones 3-9 (NC State, Wisconsin Extension); white false indigo in 5-8 and most hybrids in 4-9 (NC State). It isn't listed as invasive anywhere we checked, though it has naturalized in New England (Wildflower Center).

When to plant

Timing is counted from your average last spring frost (and first fall frost). Sow & Tell works out the actual dates for your ZIP code.

Set out nursery plants in spring or fall and pick the spot for good: a deep taproot makes baptisia drought tolerant but hard to move later (NC State, Wisconsin Extension). From seed, scarify (nick or soak in hot water) and/or give at least 4 weeks of cold before sowing; fresh seed sown outdoors in fall usually sprouts without treatment (Wisconsin Extension, Wildflower Center). Seed-grown plants take about 3-4 years to bloom, so days_to_harvest is empty.

Soil

Any well-drained soil, including clay and poor, rocky or sandy ground; NC State lists acid soil, but Wisconsin Extension says it blooms poorly in very acid soil and lime (per a soil test) can help. It needs no rich soil, since it makes its own nitrogen.

No rich soil needed: just loosen a well-drained spot. If a soil test shows strongly acid soil, add lime as it recommends, since Wisconsin Extension says baptisia blooms poorly in acid soil.

Feeding

Skip the fertilizer: as a legume it makes its own nitrogen and needs little feeding (Wisconsin Extension), and Penn State notes that overfed perennials make soft growth and few flowers. Overwatering and shade make stems flop. Don't try to move an established plant; the taproot resents it.

Harvest

Blooms mid to late spring for 2-3 weeks, about a month after the leaves come up (Wisconsin Extension). Cut stems for the vase as the spikes open. Leave the black pods for winter interest and dried arrangements, or cut the plant back by about a third after bloom (or snip just the spent spikes) to stop flopping and self-seeding (Wisconsin Extension, NC State).

Varieties (18)

Variety	Type	Notes
Starlite Prairieblues ('Starlite')	B. x bicolor (B. australis x B. bracteata)	Violet-lavender buds open to periwinkle flowers with butter-cream keels; a low, broad plant about 3 ft tall and 4 ft wide.
Twilite Prairieblues ('Twilite')	B. x variicolor (B. australis x B. sphaerocarpa)	Smoky violet-purple flowers with a lemon-yellow keel on a big plant, about 4.5 ft tall and 5.5 ft wide in Mt. Cuba's trial.
var. minor (dwarf blue false indigo)	Blue false indigo (B. australis), botanical variety	A smaller form only 1-2 ft tall, good for small gardens; native from Iowa and southeast Nebraska to Texas.
Pink Truffles	Decadence Deluxe series hybrid	Soft pink flowers on a compact, 2-3 ft plant.
Blueberry Sundae	Decadence series hybrid	Rich blue flowers on a compact plant, about 2.5-3 ft tall and wide.
Lemon Meringue	Decadence series hybrid	Bright lemon-yellow flowers on a compact, bushy plant about 3 ft tall.
Sparkling Sapphires	Decadence series hybrid	Deep blue flowers on a compact, 2-3 ft plant.
Vanilla Cream	Decadence series hybrid	Cream-colored flowers on a compact, 2-3 ft plant.
Cherries Jubilee	Decadence series hybrid (B. x variicolor)	Flowers open maroon and yellow and age to gold; about 3 ft tall and 4 ft wide.
Blue Towers	Hybrid false indigo	Lots of blue flower spikes on a big plant, nearly 5 ft tall and wide.
Dutch Chocolate	Hybrid false indigo	Compact plant about 3 ft tall and 4.5 ft wide.
Lunar Eclipse	Hybrid false indigo	Pale lemon-cream flower spikes that blush lilac and age to deep violet-purple.
Purple Smoke	Hybrid false indigo	Smoky lavender flowers on 18-inch spikes over gray-green leaves and nearly black stems; 3-5 ft tall and wide.
Purple Towers	Hybrid false indigo	Lavender flowers on spikes about 2 ft tall.
Carolina Moonlight	Hybrid false indigo (B. sphaerocarpa x B. alba)	Soft butter-yellow flowers over blue-green leaves; 3-4 ft tall and wide.
Ivory Towers	Hybrid of white false indigo (B. alba)	Pure white flowers on tall spikes, about 4 ft tall and 4.5 ft wide.
Wayne's World	White false indigo (B. alba var. alba)	White flowers on a large plant, about 4.5 ft tall and 5 ft wide.
Screamin' Yellow	Yellow wild indigo (B. sphaerocarpa)	Compact plant with bright yellow flower spikes, about 3 ft tall and 4.5 ft wide in trial.

Pests to watch for

Blister beetles

In the kitchen

Safety: All parts are poisonous if eaten, though the risk is rated low: the alkaloids baptisin and cytisine can cause nausea, vomiting and diarrhea, and children are most at risk (NC State, Wildflower Center). Don't let kids play with the rattling seed pods as food. It doesn't cause skin rashes (NC State).

Pets: Not listed by the ASPCA (no baptisia, false indigo, wild indigo or blue false indigo entry on its dog, cat or horse lists). NC State lists it as a low-toxicity problem for cats, so keep pets from chewing the plant or pods.

Sources

Photo: Photo: Agnieszka Kwiecień, Nova / Wikimedia Commons, CC BY-SA 4.0 (CC BY-SA 4.0). Photo resized for the web.

Planting dates and advice are general guidance; check with your local Cooperative Extension office for your area.