Now is the time to prune tree peonies
Rosie Lerner, Extension Consumer Horticulturist, Dept of Horticulture & Landscape Architecture, Purdue University
Tree peonies are semi-hardy woody shrubs in our area and typically suffer some dieback during the winter. Early spring is an excellent time to assess winter's toll and prune to remove damaged stems. For minor dieback, cut back to just above a healthy bud or branch. Some stems might be best removed low to the ground, particularly following severe winters or if plants are overgrown and crowded.
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Where to prune