Arisaema triphyllum aka Jack In The Pulpit

Arisaema triphyllum is a woodland perennial called jack-in-the-pulpit. It belongs to the arum family, Araceae. Its native range spans central and eastern Canada and the United States. It grows in moist woods and beside creeks. Wet woods, bogs and swamps also provide habitat. Plants grow upright from an underground storage organ. Small cormlets help them spread and form colonies.

Garden plants usually reach 1–2 feet [0.30–0.61 m] tall. NC State lists heights up to 2.5 feet [0.76 m]. Missouri Botanical Garden gives a spread of 1.5 feet [0.46 m]. Each plant bears one or two green leaves on long stalks. Each leaf has three leaflets with smooth edges. The large leaves shade the flower below them. The stalk is fleshy, and the leaves have a glossy surface. Many plants lose their leaves and go dormant by midsummer.

The flower display appears in spring, from March through May. A hooded spathe wraps around the upright spadix. Tiny green to purple flowers grow on this central spike. The hood may be green or purple, with pale stripes. Flies and gnats pollinate the flowers as they crawl inside. Plants can change from male to female between years. Older plants may bear both male and female flowers. Bright red berries form in clusters as the hood fades. Fruit can remain on display from June into October. Each berry holds one to five seeds. Songbirds and eastern box turtles eat the fruit.

Grow it in partial or full shade with rich soil. Keep the soil moist, with plenty of organic matter. It tolerates wet ground but grows poorly in heavy clay. NC State lists acidic soil and good drainage as suitable. Missouri Botanical Garden places it in USDA zones 4–9. It suits woodland beds, native gardens and rain gardens. Leave established plants undisturbed, and retain winter leaf cover. Divide plants or raise them from seed. Seeds may need two years to sprout. Seed-grown plants may take five years to flower. Sources report no major pest or disease problems. Deer tend to avoid its leaves.

All parts can poison people if eaten. Calcium oxalate crystals cause mouth pain, swelling and drooling. The plant also harms dogs, cats and horses. Pets may vomit or have trouble swallowing after chewing it. The red fruit is not edible. PFAF reports food uses for roots after extensive drying or cooking. This does not make raw roots safe to eat. PFAF also records medicinal uses, but warns against unsupervised internal use. Root starch has served as a cloth stiffener. That starch can cause blisters and swelling on hands.