When Should Asian Lilies Be Trimmed?

Asiatic lilies don’t require pruning, as they can be left on the plant when their stems and foliage are green. They should be deadheaded during the growing season to keep them blooming and then cut back in fall for winter dormancy. Deadheading occurs during late spring and early summer when the blooms begin to fade. Pruning involves inspecting the plant, removing dead or damaged stems, cutting back after flowering, and disposing of pruned material.

When the flowers have died back, the stem should be cut down to about 6 inches above the ground. If living in areas with mild winters, the stem can be left. To promote new growth and prevent leggy plants, cut back the dead blooms at the base of the plant. Trimming the stem back to about 6 inches is a simple rule of thumb.

In the fall, when leaves die back, energy is sucked down into the plant. To promote prolonged bloom, gently remove each spent flower as the petals begin to fade. Remove yellow or browning stalks in late fall after the first frost and cut dead growth at the base of the plant using shears to make 45-degree snips. The top part of the plant can be removed just below where the last petal stalks join the stem.

If the plant is in too much shade, dig it up and plant it in a sunny location for the next season. Cut the lilies back in fall after the first frost of the year, when the foliage is dead and comes off easily with pulling. If it doesn’t, cut back the stem.