There are just a few easy steps to peony division. Dig area around the plant with a sharp spade. You are going to sever some roots. It’s okay--the plant will survive. Gently remove the clump from the ground and set on a drop cloth or hauling bag. Place two forks, back-to-back, in the center of the clump. Pry apart the clump into two pieces. Continue dividing each of the pieces, making sure each division section has a shoot to grow upward and roots to grow downward. (Or you can plant larger divisions, for bigger plants.) Each division should have at least three eyes.
Remove any dead or woody parts of the plant. Also, clip back about half of the foliage on the plant so that it doesn’t compete with the root system for growth. Immediately plant the divisions. You can place the mother plant back in the spot she was occupying before the division.
Water and foliar fertilize each division well. In areas that receive frost, mulch around the base of the plant with shredded bark or leaves. Continue to water well (to help roots grow strong) until the ground freezes.
Supporting peonies Because peonies grow so quickly, they need a little additional support. Give them a helping hand with plant supports to help keep the bush upright, rather than flopping onto the ground. As peonies come into full-blown bloom, the weight of each blossom can bow stems to the ground. Keep your top-heavy peonies from flopping by inserting traditional peony rings or grow-through supports into soil when stems emerge in spring. For peonies drooping under the weight of rain-heavy blossoms, simply insert y-stakes to bring stems to an erect position.