Catmint, also known as Nepeta mussinii, is an herbaceous perennial flower or ground cover. The plant is actually a hybrid of two species that grow in parts of Turkey and the Middle East. As such, catmint is drought tolerant and quite easy to grow in most locations. The plant is popular for use in rock gardens, borders and edging. Catmint produces lavender flowers in spring, summer and fall, and has small, tidy gray-green leaves. The plant is known to be attractive to cats, hence the common name.
Plant dormant, bare-root catmint plants in spring after the soil is workable and all threat of frost is over. Select a planting location that receives full sun to partial shade and has well-drained, sandy soil. Add 1 to 2 inches of sand to heavy soils and incorporate with a garden tiller.
Dig a hole the same depth and width as the container in which the catmint was previously grown. Place the plant into the hole, then fill the hole with soil to cover the roots. Space catmint plants at least 18 to 24 inches apart.
Water catmint thoroughly just after planting, and continue to water new plantings any time the top 3 inches of soil are crumbly and moist to the touch, usually about once per week for the first two months. Reduce watering to once every two weeks for established plants.
Apply a 2-to-3 inch layer of mulch to the soil surrounding catmint plants shortly after planting and replenish as necessary. Use shredded bark mulch or leaves for the best results. Mulch will help conserve moisture and suppress the growth of weeds.
Apply a 1-inch layer of organic compost to the soil once every two years to increase the nutrients in the soil and keep catmint plants healthy. Remove the mulch around the plants first, apply the compost, then reapply the mulch.
Cut catmint plants back by two-thirds of their height with pruning shears after flowering begins to wane in late summer or fall. This will encourage fresh foliage growth, new shoots and possibly another round of blooms before the end of fall. Failure to cut plants back will reduce flowering and cause the plant to flop over unattractively.