|Nepeta cataria – "true catnip"|
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.
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.
- Some species formerly classified as Nepeta are now in the genera Dracocephalum, Glechoma, and Calamintha .
Some Nepeta species are cultivated as ornamental plants. They can be drought tolerant – water conserving, often deer repellent, with long bloom periods from late spring to autumn. Some species also have repellent properties to insect pests, including aphids and squash bugs, when planted in a garden.
Nepeta species are used as food plants by the larvae of some Lepidoptera (butterfly and moth) species including Coleophora albitarsella, and as nectar sources for pollinators, such as honeybees and hummingbirds.
- Selected ornamental species
- Nepeta cataria (catnip, catswort) – the "true catnip", cultivated as an ornamental plant, has become an invasive species in some habitats.
- Nepeta grandiflora (giant catmint, Caucasus catmint) – lusher than true catnip and has dark green leaves and dark blue flowers.
- Nepeta × faassenii (garden catmint) – a hybrid of garden source with gray-green foliage and lavender flowers. It is drought-tolerant and deer-resistant. The cultivar 'Walker's Low' was named Perennial of the Year for 2007 by the Perennial Plant Association.
- Nepeta racemosa (raceme catnip) – commonly used in landscaping. It is hardy, rated for USDA hardiness zone 5b.
Some catmint species are also used in herbal medicine for their mild sedative effect on humans.[unreliable source?] Chemical compounds isolated from Nepeta cataria inhibit calcineurin in vitro.[relevant? ]
Teucrium chamaedrys L. and Nepeta cataria L. (Lamiaceae) can be used for the treatment of inflammation. Extracts of both species were found to inhibit calcineurin; a regulator of T-cell mediated inflammation. 
- Missouri Botanical Garden: Nepeta × faassenii. Accessed January 10, 2013
- "Nepeta". Flora of China 17: 107.
- Leon L. Bram, editorial director, Robert S. Phillips, editor-in-chief, Norma H. Dickey, special projects editor-in-chief. (1983). Funk & Wagnalls New Encyclopedia. Vol. 5. New York: Funk & Wagnalls. ISBN 0-8343-0051-6.
- Herron, Scott (2003). "Catnip, Nepeta cataria, a Morphological Comparison of Mutant and Wild Type Specimens to Gain an Ethnobotanical Perspective". Economic Botany 57 (1): 135–142. doi:10.1663/0013-0001(2003)057[0135:cncamc]2.0.co;2.
- ornamental Outlook
- msucares.com: sgnews
- Richard G. Hawke. "Chicago Botanic Garden Plant Evaluation Notes".
- "All About Catnip". Cat-World. Retrieved March 14, 2009.
- Prescott T.A.K., Veitch N.C., Simmonds M.S.J., "Direct inhibition of calcineurin by caffeoyl phenylethanoid glycosides from Teucrium chamaedrys and Nepeta cataria."Journal of Ethnopharmacology. 137 (3) (pp. 1306–1310), 2011
- Zhu J.J., Zeng X.-P., Berkebile D., Du H.-J., Tong Y., Qian K. "Efficacy and safety of catnip (Nepeta cataria) as a novel filth fly repellent." Medical and Veterinary Entomology. 23 (3) (pp. 209–216), 2009.
- Birkett M.A., Hassanali A., Hoglund S., Pettersson J., Pickett J.A."Repellent activity of catmint, Nepeta cataria, and iridoid nepetalactone isomers against Afro-tropical mosquitoes, ixodid ticks and red poultry mites." Phytochemistry. 72 (1) (pp. 109–114), 2011.
- Prescott T.A.K., Veitch N.C., Simmonds M.S.J., "Direct inhibition of calcineurin by caffeoyl phenylethanoid glycosides from Teucrium chamaedrys and Nepeta cataria."Journal of Ethnopharmacology. 137 (3), 2011.
- Jacobs, Betty E.M. (1981). Growing and Using Herbs Successfully. Pownal, Vermont: Garden Way Publishing.
- Turner, Ramona (May 29, 2007). "How does catnip work its magic on cats?". Scientific American. Retrieved February 14, 2009.
|Wikimedia Commons has media related to Nepeta.|
- GRIN Species Records of Nepeta
- USDA Plant Profile: Nepeta
- Flora of China: Nepeta'
- Flora of Nepal: Nepeta'
- Drugs.com: Catnip
- "Nepetalactone: What is in catnip anyway?"
- HowStuffWorks, Inc.: How does catnip work?
- Sciencedaily.com: "Catnip Repels Mosquitoes More Effectively Than DEET" – reported at the 2001 American Chemical Society meeting.