When to Prune a Peony

Disbudding helps produce larger peony flowers.

Peonies require only minimal pruning to produce their flush of spring flowers and lush summertime foliage. Most early-season pruning is purely for the sake of appearance and doesn't affect the health of the plant. The most important pruning takes place in fall and is a vital part of ensuring your peonies remain healthy and productive for decades.

Disbudding

While not necessary, disbudding helps the plant produce the largest flowers possible. Remove the side flower buds, called lateral buds, once they are the size of a pea in spring. Inspect each flower stem for lateral buds and pinch them off once they are large enough. Leave the terminal bud, which forms at the top of the flower stalk, in place. The terminal bud produces a larger flower since energy and nutrients aren't diverted to forming flowers on the lateral buds.

Deadheading

After the flowers begin to wilt, prune them off the plant. This process, known as deadheading, does more than improve the appearance of your peonies. Deadheading allows the plant to use its nutrients and energy for healthy foliage growth instead of seed production. Cut out the flower heads 1/4 inch below the swollen section at the base of the flower. Don't remove foliage at this time, as leaf removal can jeopardize the plant's health.

Cut Flowers

Peonies make excellent cut flowers, but the flowers must be trimmed from the plant correctly so the health of the plant isn't endangered. Cut the flower stem just above the topmost set of leaves once the buds begin to open but before the flower opens fully. Do not remove foliage when cutting flowers for indoor arrangements. Remove no more than one-third of the flower stems for cut flowers, as removing too many blossoms impacts the plant's health.

Fall Pruning

Prune back the entire peony plant in fall once the foliage begins to die back naturally. Cut all stems and leaves back to ground level. Remove all the pruned foliage from the peony bed and dispose of it. Also dispose of any summer mulch in the bed. Peonies do not require a winter mulch. Dead plant material and mulch provides nesting material for disease organisms and pests over the winter, so they should not be left in the bed.

References

• North Carolina Extension; Peonies for the Home Landscape; Erv Evans; February 1999
• Purdue University Extension; The Peony: State Flower of Indiana; Michael N. Dana, et al.; May 2001