One of the best features of hybrid lilies is that they multiply, providing new plants to enlarge the perennial garden every three to five years. Replant lilies in the fall or after they've bloomed in the summer. Avoid replanting them in spring because it's easy to break off their growing stems, losing a season of bloom. Whether you lift and divide or just want to move lilies, they should be kept cool and moist; they are living and preparing for growth next year throughout the move.
Place lily bulbs in a moist, cool environment if their new homes are not ready. Set them in moist peat moss on a plastic bag or shoebox in a cool, shady place, in an unheated garage--or in a refrigerator vegetable bin in summer.
Replant your lillies in a sunny area if you are starting a new bed, using a garden spade. Cultivate it to a depth of about 12 inches. If the soil is heavy or drains slowly, work in 2 inches or more of well-rotted compost or manure, using a garden fork.
Dig new holes for lilies about a foot apart for Asiatic or other smaller bulbs. Plant larger lilies like Oriental hybrids 18 inches apart. Dig holes according to the height of the bulb. The tips of small bulbs must sit at least 3 inches below the soil surface; large bulbs should sit 4 to 6 inches below the surface. Dig holes wide enough to be able to spread out the roots growing from the bottom of the bulb.
Dust bulbs that have been divided, scaled or injured with a fungicide to protect the bulb from disease and set it into the planting hole, spreading the basal roots around it. Try to avoid breaking any roots.
Mix the fill soil with an equal measure of compost or manure if you have not amended the soil when you cultivated the new lily bed. Fill the holes and water the newly-planted bulbs deeply. Water them if the area dries out, but don't overwater and encourage mold or fungus growth. Your lilies need about an inch of water a week, including rainfall.