Nepeta is a genus of flowering plants in the family Lamiaceae known commonly as catmints. The genus name is reportedly in reference to Nepete, an ancient Etruscan city. There are about 250 species. The genus is native to Europe, Asia, and Africa, and has also naturalized in North America. Some members of this group are known as catnip or catmint because of their effect on house cats – the nepetalactone contained in some Nepeta species binds to the olfactory receptors of cats, typically resulting in temporary euphoria.
Most of the species are herbaceous perennial plants, but some are annuals. They have sturdy stems with opposite heart-shaped, green to gray-green leaves. Nepeta plants are usually aromatic in foliage and flowers. The tubular flowers can be lavender, blue, white, pink, or lilac, and spotted with tiny lavender-purple dots. The flowers are located in verticillasters grouped on spikes; or the verticillasters are arranged in opposite cymes, racemes, or panicles – toward the tip of the stems. The calyx is tubular or campanulate, they are slightly curved or straight, and the limbs are often 2-lipped with five teeth. The lower lip is larger, with 3-lobes, and the middle lobe is the largest. The flowers have 4 hairless stamens that are nearly parallel, and they ascend under the upper lip of the corolla. Two stamen are longer and stamens of pistillate flowers are rudimentary. The style protrudes outside of the mouth of the flowers. The fruits are nutlets, which are oblong-ovoid, ellipsoid, ovoid, or obovoid in shape. The surfaces of the nutlets can be slightly ribbed, smooth or warty.