Aconitum uncinatum aka Southern Blue Monkshood

Aconitum uncinatum is a perennial in the buttercup family. Gardeners call it eastern or southern blue monkshood. Its native range runs from Illinois across the eastern United States. It grows in open woods, on damp slopes, and beside streams. Mountain sites form much of its range in North Carolina. It also occurs in the Piedmont. Five states list it as endangered. North Carolina lists it as vulnerable.

This slow-growing plant has a loose, climbing or creeping form. Its stems reach about 5 feet [1.5 metres] long. The thin, green stems branch but need nearby plants for support. They lean against other plants or wind through shrubs. Smooth green leaves grow in an alternate pattern along the stems. Each leaf has three to five lobes and toothed edges. The leaves measure about four to six inches across. The foliage dies back before new growth returns.

Blue to purple flowers form racemes at the stem tips. Each flower has five sepals and two small petals. The upper sepal makes a hood over the petals. Flowers measure about an inch long. North Carolina State gives a bloom season of August through October. Chicago Botanic Garden records flowers as early as July. Bees visit the blooms, and butterflies use their nectar. Dry fruits follow from September through November. These small follicles split apart when ripe.

Grow this plant in moist soil with dappled or partial shade. Keep its roots out of strong midday sun. Chicago Botanic Garden also lists full sun as suitable. It accepts sand, loam, and heavy clay when moisture remains available. Reported USDA hardiness ranges differ: Chicago lists zones 4–7, while North Carolina State extends through zone 8. Use it in woodland gardens, shaded borders, or near ponds. Its late flowers can add color among shrubs. It also suits containers and provides cut flowers. Raise new plants from seed or divide dormant clumps.

Deer and rabbits tend to leave this plant alone. Crown rot, powdery mildew, and verticillium wilt can occur. All parts are highly poisonous, and none are edible. Eating it can cause severe illness or death. It also poisons cats and dogs. Skin contact can cause numbness, so wear gloves when handling it. Past medicinal use does not make home treatment safe.