Amaryllis bulbs are left in the ground when planted in frost-free zones and are removed from the ground before the first frost in colder climates. The United States Department of Agriculture hardiness zones 9, 10 and 11 are appropriate for year-round outdoor planting of amaryllis.
Amaryllis withstands short freezing periods, and proper precautions allow for year-round planting in USDA zone 8. To ensure survival of the plant, the bulbs require removal from the ground during the winter months in areas with colder temperatures than zone 8. The bulbs are brought inside and dried in preparation for replanting in the spring, or are placed into a pot for indoor growth.