Summer-flowering Asiatic lilies are low-maintenance compared to other garden lilies. They do not require staking, are hardy in most areas, and do not require high soil fertility or quality to thrive. These aromatic blossoms will decline after three years in the garden if the bulbs become crowded. Avoid this decline by splitting, or dividing, the lily bulbs. A benefit of this process is that you end up with additional Asiatic lily bulbs to expand you garden bed.
Cut back the foliage to ground level once it yellows and dies back naturally. This occurs in the fall, often near the first light frost.
Loosen the soil around the lily bulbs with a hand-held cultivating fork. Slide a trowel into the loosened soil and under the bulbs. Lift the bulbs out of the soil.
Brush the excess dirt off the bulbs and inspect the bulbs for the bulblets, which are small bulbs attached to the main lily bulbs. Twist the bulblet and bulb in opposite directions until they snap apart. Dispose of any bulbs or bulblets with soft spots or other signs of rot and disease.
Plant the divided Asiatic lily bulbs and bulblets immediately after splitting. Plant each bulb 3 to 4 inches deep and space them 8 inches apart. Plant the bulbs so the flat side is on the bottom of the planting hole.
Water the lily bed after replanting until it is moist to a 6-inch depth. Lay a 2- to 4-inch layer of mulch over the bed to protect the bulbs from winter temperature fluctuations as well as to preserve moisture in the soil.