Arisaema tortuosum aka Arisaema

Arisaema tortuosum, commonly called the Whipcord cobra lily, is a striking tuberous perennial in the arum family (Araceae) native to the Himalayan region. Its accepted name is Arisaema tortuosum (Wall.) Schott, with Arum tortuosum Wall. and Arisaema curvatum Hook. recognised as synonyms. The species is distributed across northern India, Pakistan, Nepal, Bhutan, Sri Lanka, Myanmar, and southern and western China, where it grows in open Rhododendron forests, scrub, and alpine meadows at elevations of roughly 1,500-3,000 metres.

The plant emerges each spring from an underground tuber. Young shoots are around 50 cm tall, but established clumps can eventually reach up to 2 m, making this one of the larger Asian Arisaema species. A fleshy, mottled petiole supports one or two palmate leaves carried near the top of the stem. The most distinctive feature is the inflorescence: a green or occasionally purple-tinged jack-in-the-pulpit spathe from whose mouth a long, whip-like spadix appendage rises and arches outward, sometimes up to 30 cm in length. Flowers may be male or bisexual, the species is monoecious, and pollination is carried out chiefly by flies. Successful pollination produces tightly packed clusters of berries that ripen from green to bright red in autumn. Flowering is generally reported from May to early June.

In cultivation A. tortuosum is grown as a hardy summer-leafing perennial in temperate gardens. It is reported as hardy in approximately USDA zones 6-9 and UK hardiness zone 7. It tolerates a wide range of light from full shade to full sun and grows in light or medium (loamy) soil that is well-drained but stays evenly moist during the growing season; soil pH from mildly acid to basic is acceptable. Tubers go dormant in winter and may be lifted and divided then; the species is also readily raised from fresh seed sown in a cold frame, with stored seed germinating over one to six months at around 15 °C.

All parts of the plant, like other Araceae, contain calcium oxalate raphides. Raw tubers cause intense burning and needle-like irritation of the mouth and throat if chewed, so the plant is treated as toxic to humans and pets unless thoroughly processed; in parts of Nepal tubers are boiled and mixed with lime juice or fermented in pits to render them edible. The species also has a long ethnobotanical record in Himalayan veterinary medicine — roots used as a cattle vermifuge, tuber juice on parasite-infested wounds, and dried tuber powder on snake bites — and modern peer-reviewed studies have isolated bioactive lectins from its tubers and leaves with documented antiviral, anticancer, antimicrobial, antioxidant and anti-inflammatory activity. Tubers are also reported to have insecticidal properties. The species is not currently assessed by IUCN (category NE) and is not listed in the Global Invasive Species Database.