Colorful, short blooming peonies are a favorite of many perennial gardens. While the flowering period is short, the lush green foliage adds attractive ground cover around flower annuals and spring bulbs. Peonies are also cold hardy and require no special care in areas where the thermometer often dips below freezing. Long lived, peonies rarely require dividing---perhaps every 15 years but it isn't a necessity unless you want to enlarge the peony bed. When dividing the bulb, actually a tuberous root system, is cut apart and replanted.
Plan your division for fall---usually mid-September through October. Prepare a well drained garden bed in full sun to plant the division into.
Dig around the peony plant, digging 6 inches away from the main plant. Dig down to an 8-inch depth then lever your spade under the roots to lift them out without damaging them.
Brush off excess dirt from the roots. Rinse of excess soil with a running water. Do not soak the roots as this leads to rot.
Study the top of each root section to find the eyes and decide where to make your cuts. Divide so each section as between three and five eyes. Eyes look like small pink fleshy protrusions and are similar to potato eyes.
Cut apart each root where you decided using the tip of your spade or a sharp knife. Discard any roots sections that are damaged or show signs of rot such as soft spots.
Replant the cut root sections, eyes facing up. Plant so the top of the root is 2 inches beneath the soil surface and space plants 2 to 3 feet apart.