Millions of Easter lilies (Lilium longiflorum) are sold each year throughout the United States and Canada. The Easter lilies that you buy in containers have all been grown in greenhouses and carefully manipulated so they will be in bloom at Easter time; although, these pure white, perfumed lilies normally bloom outdoors in midsummer. Too many people, however, do not seem to realize that Easter lilies, which are hardy to zone 5, can be planted in the garden after the blooms are spent and will provide them with fresh blooms for many years.
Allow the Easter lily to die back completely after the blooms are spent. Do not cut the stems back before this time, since this is the way lilies take in nutrients for the next year's growth. You can set the pot outside in partial shade until the leaves and stems are completely dead.
Cut back the stems to the soil level. Once the stems and leaves have died back completely, you can then cut the stems back to the ground. This will usually be in the late summer or early fall.
Dig a planting hole in partial shade. The hole should be as deep as three times the size of the bulb. The planting hole should also be in an area where the Easter lily receives morning sun and is protected from the hot afternoon sun.
Work two to three handfuls of the humus into the planting hole. If you have your own compost, you can use that instead. Easter lilies like humus-rich, well-drained soil.
Cover the bulb and add a good granular, time-released fertilizer following the instructions on the back of the package.
Mulch. Add about 3 inches of mulch to protect the bulb during the winter months.
Water deeply. Set your sprinkler to water the bulb for about 20 minutes. This will give the Easter lily a deep drink of water, which is better for its deep roots than short shallow watering.