Crocus grows from a bulb-like structure known as a corm. These spring-blooming perennials are one of the first flowers of the season, according to Clemson University extension. The crocus survives and flowers for many years in the flower garden. Eventually the bed becomes crowded, so the corms must be dug, divided then transplanted into new beds. You may also need to dig and transplant the corms to a new bed as your landscape design changes. When possible, transplant your crocus bulbs in fall about six weeks before the first expected frost.
Loosen the soil around the crocus with a handheld cultivating fork. Slide a trowel under the corms and lift them from the soil.
Brush the excess soil off the corms and inspect them. Twist apart any that are connected. Dispose of any that have open wounds, appear shriveled or have soft spots indicating rot.
Spread a 2-inch layer of compost over a well-draining, full-sun garden bed. Apply a slow-release balanced fertilizer to the bed at the rate recommended on the label, then work both the compost and fertilizer into the top 6 inches of the soil.
Plant the crocus so that the top of each corm is 3 inches beneath the soil surface. Space the crocus 3 inches apart in clusters of five to seven corms.
Water the bed thoroughly after transplanting, wetting the soil to a 6-inch depth. Cover the bed in 2- to 3-inches of straw mulch, which preserves moisture and prevents frost damage over the winter months.