Growing Baptisia (Wild Indigo)
Latin Name Pronunciation: bap-tiz'ee-uh
These substantial plants are very long-lived and vigorous. Initially a bit slow to establish, Baptisias are also tough and drought tolerant, requiring little maintenance. These members of the Pea family have lupine-like flowers ideal for cutting and are very hardy to zone 3. They grow three to four feet tall and as wide, with lovely blue-green foliage that stays healthy all summer, providing a perfect backdrop for later blooming perennial companions. Plant 18 to 30 inches apart, depending on variety.
Light/Watering: Plants are at their best in full sun. They will tolerate some shade, but will then need staking. These plants are very drought-tolerant once established although evenly moist soil is always in a plant's best interest.
Fertilizer/Soil and pH: Baptisia prefers slightly acidic soils, so do not add lime. Well-drained, deep, rich soil is best, although Baptisia does quite well in soils of low fertility. Fertilize in early spring with a balanced fertilizer with supplemental summer applications, or use a slow-release form.
Pests/Diseases: Long-lived and healthy, Baptisias are generally free from insect pests and foliage diseases.
Companions: Baptisias bloom along with Siberian Irises and Peonies in late spring to early summer. Their attractive foliage makes them an asset even when they are not in flower.
Reflowering: Baptisias flower once in late spring and will not reflower if deadheaded, a practice which will also prevent the development of the attractive seedpods. Plants do look their best if cut back by one-third after flowering and shaped; this will eliminate any late-season floppiness.
Dividing/Transplanting: These shrub-like plants are relatively slow growing and division is not needed for ten years or so. Because of deep taproots, transplanting is difficult but can be done successfully with careful efforts, especially while plants are still small.
End-of-Season Care: The lovely foliage of Baptisia turns black with the first hard frost and the plants fall over by January, so cutting back close to the ground in late autumn during general cleanup is beneficial.
Calendar of Care - Baptisia
Early Spring: Apply a light application of balanced or slow-release fertilizer or side-dress with compost and organic amendments when new growth appears. Supplement nitrogen during periods of prolonged rain to counter natural leaching. Water well if it is unseasonably dry, as plants prefer evenly moist soil. Mulch if desired.
Mid-Spring: Plants grown in part shade will need support. Train foliage through Peony rings or tie to sturdy stakes.
Summer: Pinch off dead flowers if development of seedpods is not desired. Groom plants by removing yellowing or dead leaves. Plants can be cut back by one-third and shaped now for most attractive habit through the rest of the growing season.
Fall: Cut foliage back right above soil level.