Catmint is a common name for certain plants in the genus Nepeta, a group within the mint family Lamiaceae. It is closely related to catnip, which is also in the genus Nepeta. Both names come from the euphoric effect some members of the genus have on cats. This effect is created both by dried and living forms of those plants.
The effect on cats may be compared to inebriation in humans. It is believed to be brought on by the way chemicals from the plant mimic cat pheromones. The effect is inherited genetically, and though all varieties of felines — including lions — may experience it, specific cats may be immune to the effect.
Members of the Nepeta genus are herbaceous, meaning their stems are non-woody and die off after the growing season. Catmint is also perennial, meaning that only the parts of the plants above ground die off, and the plants grow back the following season from the underground portions. Catmint is a flowering plant, and the normal blooming season begins in early summer; the plant is capable of blooming repeatedly throughout the season.
The flowers from catnip may have some medicinal properties. In traditional applications, catmint is prepared as an infusion, which is, in simplest terms, like making tea. This may be used to treat basic cold symptoms such as a cough, though some sources caution that drinking too much catnip tea may induce vomiting. In folk remedies, catmint may be used to treat conditions as diverse as hysteria, nightmares and headaches; it may even be applied to painful swelling as a way of reducing the pain.
The recognized active chemical in catmint responsible for most of its effects is nepetalactone. This chemical is believed to be the active ingredient that allows oil distilled from catmint to be an effective insect repellent, though it may not be as effective when applied directly to the skin. The repellent properties of catmint may also be linked to the lack of problems the plants have with garden pests, and the plant may even be undesirable to deer.
In gardening, plants from the Nepeta genus may be used decoratively. The flowers can be white, pink or lavender. A key advantage of using Nepeta over other flowering plants is its inherent hardiness. The plants thrive in poor soil and do best with minimal attention and fertilization.
Catmint plants may be used as ground cover or to complement taller plants such as rosebushes. This is the result of the plant's ability to hide the lower, less attractive portions of the taller plants. In addition, catmint is often used near walkways, along walls and as edging around a green space or garden.