Herbaceous peonies (Paeonia), which have foliage that dies back during the dormant season, are quintessential perennials. They stay where you put them, live for an astounding 40 to 50 years, and require very little attention. They survive the harshest winters, easily resist drought, and aren't bothered by hungry deer or rabbits. Think of them as garden workhorses-particularly beautiful workhorses.
How to grow
Although the sight of peonies' sumptuous blooms prompts many people to buy their plants in May, peonies, just like daffodil and tulip bulbs, are best planted in fall.
For fall planting, your best bet is to put in bareroot peonies rather than green, growing plants. A bareroot peony consists of several swollen roots and a crown of pinkish growth points called buds or eyes. When you're shopping, make sure each division you buy has at least three buds and roots that are solidly attached to the crown. Plant as soon as possible, but if you must wait a few days, gently wrap each bareroot plant in moist newspaper, place it into a ventilated plastic bag, and keep the bag out of the sun. Your planting site should receive morning sun and afternoon shade.
The site should also have well draining soil and contain plenty of organic matter. If you need to add organic matter, mix composted manure or compost into the soil before backfilling the hole. If the soil is excessively acidic, add 1 cup of lime per plant.
Plant each bareroot peony so the buds, or growing points, face skyward and are about 1 1/2 inches below the soil surface. A common problem is planting too deeply.
Water well after planting and keep the soil reasonably moist until the first frost. Then pile 4 inches of mulch atop the planting hole to keep the new roots from heaving out of the ground during winter freezes and thaws. Pull the mulch away in spring. After the first year, the established plant won't need winter mulching.
Peonies grow and bloom much better if soil nutrients are replenished every year. Fertilize established peonies by spreading a 2-inch layer of composted manure or compost around the plants in late fall.
The only other care that peonies need is an end-of-the-year cleanup. This consists of cutting peonies back to the ground in late fall and destroying all the plant debris by burning it or putting it into the trash. Peony foliage should not be added to the compost pile because botrytis blight (also called gray mold), a fungal disease that affects peonies, sometimes survives the composting process.
Some gardeners are bothered by ants that are attracted to the nectar in peonies. When you cut peonies for a fresh-flower arrangement, simply wash the ants off with water.
Note: Some of the best varieties that remain handsome through summer include 'Kansas,' a double-flowered red, and 'Le Charme,' a tall Japanese form with pink flowers.
Early to midseason blooming peonies
Midseason to late blooming peonies