Care of Catnip Plants

Catnip, or Nepeta cataria, is a perennial herb in the mint family native to North America. The plant gives off an aromatic scent, which will cause what is known as the "catnip response" in most adult felines. Grow catnip far from other plants, as cats may damage nearby flora while "under the influence" of catnip. Plants can reach 2 to 4 feet in height, and produce lavender-colored flowers on tall flower spikes above the light-green foliage.

Grow plant container catnip in the late spring or early summer. Choose a planting location that receives full sun to partial shade and has a well-drained, sandy, loam soil. If you have heavy clay soil, add limestone according to the manufacturer's instructions to increase alkalinity. Dig a planting hole of equal depth to the growing container and at least twice as wide. Remove the plant from the container, place the roots into the hole and back-fill with soil.

Catnip plants may also be grown directly from seed, if desired. Sow the seeds in spring after all danger of frost has passed. Cover with about 1/8-inch of soil and germination will occur in 10 to 20 days. Thin seedlings so they stand 12 to 18 inches apart once they reach 2 to 5 inches in height.

Water plants or seeds thoroughly just after planting. Continue to water twice weekly for the first two weeks, and then reduce watering to once every two weeks after the plants are established. Increase watering to once per week or more during very dry periods or high temperatures.

Feed catnip plants every two weeks with a water-soluble flower fertilizer. Begin applications two weeks after planting and continue until the first week of summer. Do not fertilize catnip during fall or winter, as the plant will not use the nutrients. Refer to the instructions on the packaging for proper application rate.

Apply a 1 to 2 inch layer of mulch around the base of catnip plants in late fall before the first frost of winter. Mulching will help plants survive cold temperatures without dying. Remove the mulch layer in early spring, around February or March, as soon as new growth appears. Leaf mold, hay or bark mulch all work well for mulching catnip plants.

Remove spent flowers by pinching them off at the stem to prevent self-seeding. Catnip becomes scraggly after flowering and needs to be cut back. Prune plants after the first bloom to encourage a second flowering before winter. Cut catnip plants back to within 3 or 4 inches of the ground after the first frost. This will help them survive winter and encourage new, healthy growth in spring.