The bright orange flowers and lush, strap-shaped foliage of the crocosmia make this hardy, low-maintenance plant a popular addition to the landscape. Crocosmia plants are members of the family Iridaceae and grow from bulblike corms. When the flowers begin to look sparse it is a good sign that it is time to divide the corms. Dividing and replanting crocosmia is a simple but necessary part of raising healthy plants. Crocosmia are hardy in U.S. Department of Agriculture plant hardiness zones 6 to 9.
Place a garden fork on the soil about 3 inches from the edge of the crocosmia plant. Press the fork into the soil and then pull back on the handle to loosen the corms from the soil.
Place the corms on a tarp or table for division.
Brush the dirt off of the corms. Gently pull the corms apart with your fingers. Take out the small corms, called cormels, and put them aside. Divide the healthy corms from any that look old, dried up or withered.
Replant the crocosmia corms in the original spot or spread them around the garden. Space the corms 6 inches apart in holes that are 4 to 6 inches deep. Plant crocosmia in full sun or light shade, in loose soil with good drainage.
The foliage and flowers of the crocosmia die back in the fall and lay dormant during the winter months. The dead foliage can be cut back to the ground to improve appearance and make fall division easier. In Zones 5 and colder, dig out the corms in the fall before the last frost date. Remove the old corms and the cormels and discard. Store the healthy corms in a cool, dark frost-free area for the winter and replant in the spring.