Dividing Peonies

Not sure how to propagate peonies? The process for dividing peonies isn’t all that difficult. Because these are long-lived perennials, you rarely need to tackle splitting peonies. But there are occasions when you might need to deal with propagating peonies. Learn what you need to know to be successful.

Unlike many perennials, peonies don’t typically need to be divided. In most situations where these old-fashioned favorites are growing in an ideal setting, you probably won’t need to handle dividing peonies for 10 or 15 years. Explore some of the reasons why you might want to consider splitting peonies.

Because peonies are so long-lived, they’re often referred to as a heritage or legacy perennial.That’s a plant that’s passed down through generations. Sometimes you’ll want to undertake dividing peonies because of sentimental reasons. You may want a piece of a plant a relative or friend grew, or you may be planning on propagating peonies so you can save a plant on an abandoned lot.

Peonies are favorite graveside plants, and you may have a treasured peony growing near a loved one’s grave that you’d like to use as a memorial planting in your own garden. Sometimes peonies planted too closely together wind up needing divided because clumps become crowded. The bottom line on dividing peonies successfully is understanding that these plants dislike being disturbed or moved, so only do it when absolutely necessary.

It’s best to embark on splitting peonies when plants are dormant—in fall or very early spring before new growth appears. If you dig plants in spring, plants may fail to bloom for a year or two. Tackle dividing peonies in summer, and you risk interrupting the production of the plant’s internal food stores that fuel next year’s growth and blooming. The best time for propagating peonies is in autumn, after plants have become dormant.

The procedure for dividing peonies is very simple. To lift and split entire clumps of peonies, start by digging around the plant very carefully. Insert your shovel into soil just beyond the outermost leaves of the clump. Slip your shovel beneath the clump, too. Your goal is to free the plant from soil without breaking the tuberous roots.

When you can lift the peony clump out of its planting spot, shift it gently onto a tarp. Clip leaf stems to just a few inches tall. Toss healthy leaves into your compost pile. Bag peony leaves covered with powdery mildew for trash disposal.

Gently shake soil from peony roots. Transfer this soil back into the planting hole. If necessary, grab the hose and gently wash soil from the roots. Once the tuberous roots are fully exposed, start the process of dividing the peonies. Using a sharp knife, cut peonies into sections having at least three or four healthy growing buds or eyes. Sometimes you can just pull the tubers apart by hand.

Toss any tubers that are soft or diseased. If you must save them, cut out soft spots and dust the tuber with fungicide to prevent disease. Replant tubers at the right depth for your region and water. In cold regions, add a loose winter mulch over them once the ground freezes.