Learn all about growing this spring blooming, nitrogen fixing perennial in your garden.
Listen to Podcast: podcast transcript
How To Grow: Baptisia
blue wild indigo
Full sun, part sun
Bloom Period and Seasonal Color
Late spring to summer in colors of blue, white, red and yellow
Mature Height x Spread
3 to 4 feet x 3 to 4 feet
Native, attracts beneficials, drought tolerant, deer resistant
This native perennial has a shrub-like appearance even though it dies back to the ground each winter. It’s in the legume family and the pea-like leaves give away its heritage. It was once used as a substitute for make indigo blue dye. False indigo is a long-lived perennial flower in the garden with beautiful blue flowers in late spring. There are other species of false indigo with white, red and yellow flowers as well. The dark green leaves make a good backdrop to other flowers throughout the summer. The flowers give way to pea-like seedpods that turn black when mature. They’re ornamental in their own right often used in flower arranging. The seeds rattle in the pods making them fun toys for kids.
Where, When and How to Plant
False indigo is hardy throughout our region. Seeds are hard to germinate and plants started from seed take up to 3 years to flower. It’s best to purchase plants from a local garden center and plant from spring to early fall. False indigo grows best in full or part sun on well-drained, compost-amended soil. The plants have taproots so are difficult to move once planted. Space plants 3 to 4 feet apart.
False indigo likes moisture, but once established the plants are drought tolerant. Mulch to keep the soil wet and weeds away. Since it’s a legume, it needs little additional fertilizer.
Regional Advice and Care
If growing false indigo in part shade, place stakes or a cage around the plant, as the flower stalks may get floppy. If not using the seedpods for arrangements deadhead spent flowers. Once it gets cooler in fall and the leaves start turning black, cut back the whole plant to the ground. If leaves are prone to powdery mildew disease, remove weeds and other perennials close to the plant to open up the area around the plant and promote more air movement. Control aphids on the new foliage with sprays on insecticidal soap.
Companion Planting and Design
Plant false indigo in a perennial flower border near peonies, iris and salvias to compliment those flowers. Place later blooming perennials, such as daylilies and coneflowers, in front of false indigo to take advantage of the dark green foliage back drop. False indigo can also be plant as a meadow plant or in the wildflower patch.
“Purple Smoke” is a newer hybrid variety with dark purple flower stalks. “White Wild Indigo” is a Baptisia alba species with white flowers. The “Decadence Series” features red, yellow and blue colored flowers on more compact plants. “Carolina Moonlight” is a cross of two species that produced blue-green leaves and buttery-yellow flower stalks.
Excerpted from my book, New England Getting Started Garden Guide.
The blue wild indigo sounds like a great name for a movie or book, but really it’s just the name for a fabulous spring blooming perennial. Baptisia is native to the Midwest and East Coast. Another common name for it is false wild indigo because is was used as a dye substitute for the tropical indigo plant. Baptisia a tough plant that hasn’t gotten much attention from breeders, until recently. While most gardeners know Baptisia as that shrubby, blue-flowered perennial that blooms early, then is done for the season, with new varieties and proper use in a design, baptisia can fill many roles in the perennial flower garden.
In spite of its common name, blue isn’t the only color of baptisia. Yellow flowering varieties, such as ‘Carolina Moon’ and ‘Lemon Meringue’, offer 3′ tall plants with 18 inch tall spikes of golden flowers. ‘Purple Smoke’ grows 4 feet tall and has dark green foliage and dark purple flower spikes. The new Decandance series from Proven Winners offers many baptisia varieties in a range of colors. One of my favorites is ‘Cherries Jubilee’ for its bicolor maroon and yellow flowers on 3 foot tall plants.
All these baptisia are hardy to zones 4 and can grow well in full to part sun. Although they only bloom in spring, the shrubby, pea-like foliage stays green all summer providing a perfect backdrop to other, lower growing and later blooming perennials. Baptisia is a legume with a thick taproot, so it’s drought tolerant, fixes nitrogen, and breaks up clay soils. Bees love the flowers, but deer don’t like baptisia, so that’s one less perennial you’ll have to protect.