Catnip is a North American native. Nepeta is a genus containing about 250 species, all of which are recreational drugs. If you’re a cat, that is. A substance called nepetalactone produces a pleasurable and harmless “high” which effects about 50-80% of all cats (lions and tigers too!). Catnip is a member of the mint family, and is sometimes called catmint.
Identification: Plants are up to 3' (1 m) high, with square-shaped stems. Leaves are triangular to oval in shape, up to 4" (10 cm) × 2" (6 cm). Leaf edges have rounded serrations. They are green and slightly hairy above, and grayish from fine hairs below. Flowers are whorled spikes ½-3½" (1.3-8.9 cm) long, directly attached to the stem, white-to-pink, spotted with purple. Individual flowers are about ¼" (7 mm) tall, with a top lip and three bottom lobes. The fruits are small reddish-brown egg-shaped nutlets.
Medical: Catnip contains a mild sedative that was used by early Europeans to treat convulsions, coughs, sleeplessness, and anxiety, in the form of a tea. It is also sometimes used as a cold and flu remedy.
Nepeta cataria at Illinois Wildflowers
Nepeta cataria on Missouriplants.com
Nepeta cataria on Kansas Wildflowers and Grasses
Nepeta cataria on Wikipedia
Nepeta cataria on holoweb.com
Nepeta cataria on Plants for a Future, a resource and information centre for edible and otherwise useful plants
Nepeta cataria on CalPhotos
Nepeta cataria on SEINet—the Southwest Environmental Information Network
Nepeta cataria from the Jepson Manual
Nepeta cataria description by Thomas H. Kent, last updated 7 Oct 2021.