Vigorous, spreading members of the mint family with aromatic foliage. With the exception of catnip (N. cataria), these plants are valuable for their spikes of two-lipped blue or blue-violet (or sometimes pink, white, or yellow) flowers. As soon as blossoms fade, shear the plants back by half or cut faded flower stems to the ground to encourage rebloom. (Most species seed freely and can become invasive if spent flowers are not removed.)
Plants make attractive, informal low hedges or edgings. In winter or early spring, cut out last year’s growth to make way for new stems. At that time, you can also divide clumps for increase, though it’s easy to start new plants from cuttings (take them before flower buds form). When buying named varieties, be sure to obtain cutting-grown plants; seedlings vary in flower color and habit. In cold-winter climates, nepetas are occasionally used as a substitute for lavender (Lavandula) in borders and edgings. Most species resent heat combined with high humidity. In desert Zones 12 and 13, most are best treated as winter annuals. They tolerate regular moisture if the soil is well drained.
From the Mediterranean and western Asia. Grows to 2–3 ft. high and wide, with downy, heart-shaped, tooth-edged, gray-green leaves. Spikes of small (1/4–1/2-in.) whitish or pinkish flowers in late spring, early summer. Not very ornamental but worthy of a place in the herb garden. Grows easily in light soil and self-sows readily.
The common name refers to the stimulant effect on cats, but their susceptibility to the herb varies: some felines fall into a rapturous frenzy, rolling wildly on the plant, but others ignore it. If necessary, protect the crown of the plant with an inverted wire basket; stems will grow through. The same tactic also helps preserve potted plants grown outdoors and brought indoors occasionally for cats to enjoy. You can sprinkle dried leaves over your cat’s food or use them to stuff cloth toys. Some people use catnip to flavor tea.Nepeta racemosa
Native to the Caucasus, Turkey, and Iran. Sprawling plant grows from 6 in. to 1 ft. high and about 2 ft. or more wide. Roundish, scallop-edged leaves can range in shades from medium green to gray-green; they are covered with fine hairs. The typical form produces 1⁄3-in.-long lavender flowers for a short period in midsummer; may rebloom if sheared. Reseeds prodigiously. Inferior to its hybrid N. x faassenii, but several worthwhile selections are more compact than the species and bloom over a longer period. ‘Blue Ice’ has dense gray-green foliage and pale blue flowers that fade to near-white. ‘Superba’ has a dense, matlike habit and gray-green leaves that are smaller than those of the species; it bears lavender-blue blossoms from spring through fall. ‘Walker’s Low’ grows 2–3 ft. high and has vivid lavender-blue flowers (sometimes sold as N. x faassenii).
Native to Armenia and the Caucasus. May be a form o fN. racemosa. Makes a thick, low mound to 1 ft. high and 2–4 ft. wide. Woolly, heart-shaped, deeply veined leaves have pointed tips and scalloped edges; they are pale green above, gray or white beneath, 3/4–1 1/4 in. long. Blooms from late spring through fall, producing 6–8-in.-high spikes of deep blue flowers with just a hint of violet. Good groundcover; space plants 3 ft. apart.Nepeta sibirica
Native to Siberia. Sturdy, upright habit to 2–3 ft. high and 1 1/2–2 ft. wide. Dark green, oblong to lance-shaped leaves are softly hairy beneath. Spikes of large (1 1/2 in.) violet-blue blossoms appear for about a month, beginning in early summer. ‘Six Hills Giant’ is possibly a hybrid of N. x faassenii—but grows taller (reaches 2 1/2–3 ft. high and as wide), has greener foliage, and bears deeper blue flowers. More tolerant of damp climates than other nepetas. ‘Souvenir d’André Chaudron’ (‘Blue Beauty’) is similar but grows to only 1 1/2 ft. high and blooms for a longer period, with the season extending into late summer.
Sterile hybrid of N. racemosa and a European species; often sold as N. mussinii. Soft, silvery gray-green, spreading mound grows to 1 ft. high and 1 1/2–2 ft. wide. Scallop-edged, heart-shaped gray-green leaves to 1 in. long. Attractive to some cats, who enjoy nibbling on and rolling in plantings; insert short sticks in the ground among the foliage to discourage cats and prevent destruction. Loose, lax spikes of 1/2-in., lavender-blue flowers in late spring, early summer.
‘Select Blue’ has darker flowers than the species; ‘Snowflake’ has pure white blooms. ‘Dropmore’ grows to 1 1/2 ft. high and 3 ft. wide; it may be a hybrid involving another species.
Set plants 1–1 1/2 ft. apart for groundcover.
European native for rock gardens or naturalizing. In bulb and leaf, resembles small hyacinth, but 10-i...
Grows to 2 ft. tall. Smooth deep green leaves with yellow variegation have a spicy apple fragrance and...
Variable hybrid with erect or spreading growth to 1 ft. high and 2 ft. wide. Ovate to lance-shaped, me...