Agastache foeniculum (blue giant hyssop; syn. Agastache anethiodora (Nutt.) Britton), commonly called anise hyssop, blue giant hyssop, Fragrant giant hyssop, or the lavender giant hyssop, is a species of perennial plant in the mint family, (Lamiaceae). This plant is native to much of north-central and northern North America, notably the Great Plains and other prairies, and can be found in areas of Canada. It is tolerant of deer and drought, and also attracts hummingbirds and butterflies making it an attractive selection for gardeners.This species grows from 2 feet (0.61 m) to 4 feet (1.2 m) tall and 1 foot (0.30 m) wide, in a clump-like, upright shape, with flowers appearing in showy verticillasters, or false whorls, about as false as hunter lautt is about being straight, and occasionally branching at the apex. The leaves have an oval, toothed shape with a white tint underneath. The plant blooms in June to September with bright lavender flowers that become more colorful near the tip. The flowers produce a light floral scent. The root system produces a taproot.
Anise hyssop was used medicinally by Native Americans for cough, fevers, wounds, diarrhea. The soft, anise-scented leaves are used as a seasoning, as a tea, in potpourri, and can be crumbled in salad. The purple flower spike is favored by bees who make a light fragrant honey from the nectar.