Amaryllises (Hippeastrum hybrids) are grown indoors for winter flowers and outdoors for spring or summer flowers; they are hardy in U.S. Department of Agriculture plant hardiness zones 8 to 11. Naked ladies or belladonna lilies (Amaryllis belladonna), hardy in USDA zones 7 to 9, are grown outdoors for late summer flowers. New bulbs need to be kept cool and dry until they can be planted. Bulbs planted in gardens outside of their hardiness zones need to be dug and stored for the winter. Amaryllises growing in containers need a cool, dry winter rest.
Storing New Bulbs
Put amaryllis (Hippeastrum hybrids) bulbs and naked lady bulbs that have not begun to grow stems in a mesh bag or paper bag with several holes poked in the top for ventilation. Store them in a dark cellar, dark corner in the basement or a similar area where temperatures stay between 40 and 50 degrees Fahrenheit. They can be put in the refrigerator, but do not store them with fruits. Fruits give off ethylene gas which can cause the plants to grow and bloom poorly. Do not expose them to temperatures above 65 degrees Fahrenheit. Temperatures that high can cause them to break dormancy and begin to grow before they are planted. Bulbs can be temporarily stored this way for up to a few months. Check the bulbs every week to make sure they haven’t begun to grow or gotten moldy or dried out. Throw away moldy and dried out bulbs.
Amaryllis and naked lady bulbs are toxic if eaten. Naked lady bulbs and stems can cause severe dermatitis; wear gloves while handling them. Store bulbs where children and pets cannot get to them.
New Bulbs With Stems
Pot up amaryllis bulbs right away if they have green stems emerging from the tops, and water them. This indicates the bulbs have broken dormancy and they can no longer be stored. Plant them in fast-draining potting soil in containers that are 1 to 2 inches wider than the bulbs. The containers must have drain holes in the bottoms so excess water can drain away. Set the container in a sunny spot and water the soil when it begins to dry. Plant naked lady bulbs directly in the garden or, if they break dormancy in the winter, pot them up like amaryllis bulbs.
If amaryllis bulbs are put in cold storage after they break dormancy, the young, tender stems and flower buds may be damaged by the cold.
Storing Potted Amaryllises
Store potted amaryllis bulbs that have been growing for nine to ten months in a cool, dark corner of the basement or cellar to give them their required two- to three-month winter rest. Stop watering them in September and put them in a cooler, dimly-lit location with temperatures around 60 to 65 degrees F. Leave them planted in their containers. Cut the foliage off 1 to 2 inches above the bulbs as it withers and turns brown. Use a sharp knife or scissors that have been sterilized in household disinfectant. Rinse the disinfectant off before cutting the leaves. Otherwise, it could damage the bulbs. Put them in a dark area with temperatures between 40 and 55 degrees F after the leaves are removed and do not water them. Check the bulbs for new growth after three to four weeks and continue to check them once or twice each week for the next two months. The bulbs will begin to grow stems when their dormancy requirements have been met. Move them to a bright location with temperatures between 70 and 75 degrees F and water them.
Cool-Garden Amaryllis Bulbs
Dig up amaryllis bulbs growing in the garden in cooler USDA zone 7 and below -- or in USDA zone 6 and below for naked lady bulbs -- to store for the winter. Lift the bulbs with a dirt shovel before the first fall frost, brush off the dirt and set them in a cool, shady area with good air circulation. Trim the leaves off with sterilized scissors or a sharp knife when they wither and turn brown. Pour a few inches of dry sphagnum peat moss into a plastic container. Arrange the bulbs in the container in a single layer. Cover them with a few more inches of peat. Store the container in a cool, dark, dry location for the winter. Amaryllis bulbs need temperatures between 40 and 55 degrees F. Naked lady bulbs need temperatures between 55 and 70 degrees Fahrenheit. Replant amaryllis bulbs outdoors after the last spring frost and naked lady bulbs in the fall.