Peonies, long-lived perennials native to Asia, Europe and North America, produce single, double or semidouble blooms in shades of red, pink, white and yellow during spring. Peonies also provide attractive foliage throughout the summer months after the flowers fade, which often acts as a backdrop for annual flowers or other late-blooming perennials. Once established, peonies require only minimal care and live up to 50 years in a single location. Reaching 4 feet in height, peonies make a dramatic statement when used as accent plants or mass plantings in beds and borders.
Plant peonies during early fall before the first frost of the season. Select a location that receives a minimum of six hours of bright sunlight each day and consists of well-drained, fertile, moist soil. Spread a 2- to 3-inch layer of organic compost over the planting site and use a shovel to incorporate it into the soil before planting.
Dig a hole in the soil for each peony just large enough to house the root system without crowding. Insert the roots into the hole, cover with soil and water lightly to collapse any air pockets. Space peonies 24 to 36 inches apart for the best results.
Apply a 2- to 3-inch layer of mulch to the ground surrounding peonies to insulate the soil, prevent cold damage, deter weeds and improve moisture retention. Start the mulch at least 3 inches from the plants to reduce the risk of fungal diseases. Remove the mulch the following spring when new growth begins.
Water peonies during the spring, summer and fall months about once per week, allowing the soil to dry moderately between applications. Soak the soil to a depth of 6 to 8 inches at each watering to ensure the plant receives plenty of moisture.
Feed the plants once per year during early spring, when the shoots reach about 3 to 4 inches in height. Use a balanced 10-10-10 NPK fertilizer to provide nutrition for root, flower and foliage development. Check the manufacturer's label for application instructions. Water immediately after fertilizing to prevent root burn.
Cut peony stems back to ground level during fall when the foliage yellows or dies from frost. Repeat every year of growth to maximize flowering the following year.
Stake tall varieties when they grow too large to support themselves. Insert a stake into the ground near the plant and loosely secure the plant to it with twine to hold the plant in place. Use a stake, wooden dowel or straight branch roughly 6 inches shorter than the mature plant.