Catnip

mint family, Lamiaceae, the members of which are known as catnips or catmints, and which includes the Common Catnip beloved of most cats.

At least three species of catnip smell of cat urine:

• Nepeta cataria (Mentha cataria), Catnip, True catnip, Catmint, Field balm. This is an attractive 50–80 cm (1.5–3 ft) tall herb resembling mint in appearance, with greyish-green leaves and white flowers.
• Nepeta grandiflora, Giant catmint, Caucasus catmint. It is lusher than true catnip, and has dark green leaves and dark blue, almost purple flowers.
• Nepeta faassenii, Faassen's Nepeta, Faassen's catnip, Catmint. This species is far smaller than either of above, and is almost a ground cover. It has with greyish-green leaves and light purple flowers.

Of these, both true catnip and Faassen's catnip have a sharp, biting taste, while the taste of giant catmint is bland.

There are dozens, if not hundreds, of catnip species. Also, some Dracocephalums, Glechoma hederacea and some Calaminthas used to be Nepetas.

There is a lemon-scented cultivar of true catnip, Nepeta cataria 'Citriodora'. It looks exactly like true catnip, but it has the scent of and can be used like lemon balm.

Catnip and catmint got their names from the unusual behaviour of domestic cats when they smell the bruised leaves or stems: purring, salivation etc. It is not known why cats respond in this way to catnip, but studies have identified the component chemical in catnip as a lactone compound called nepetalactone. Recent research has speculated that exposure to catnip has a narcotic effect on felines, inducing symptoms such as hallucinations.

The root of a completely unrelated plant, valerian, has a similar effect on cats, but it is not known what constituent in valerian would be responsible for this behavior.

Medicinal uses

Herbally, catnips are used as relaxants, nervines, sedatives, and as antispasmodics. Use them in tea if you have trouble sleeping, if you're stressed, and if you have menstrual cramps, or gut cramps from something you've eaten.

Tea: Take 1 teaspoon dried herb or 2 teaspoons fresh herb (aboveground parts, in or out of flower) to 2 dl (½ pint) boiling water, let steep 5–10 minutes, strain out the plant parts, drink 1-2 cups as needed.

Research from the Iowa State University has found that an oil—nepetalactone—extracted from catnip (Nepeta cataria) has been found to be nearly 10 times more effective at repelling mosquitos than DEET.