It is a myth that ants are necessary to permit peonies to bloom. A common problem of peonies is the failure to bloom. It may be the result of planting too deeply, immature plants, excess nitrogen, inadequate sunlight, overcrowding, nutrient deficiency, insect or disease problems, competition from roots of nearby plants or late freezes. Some cultivars will fail to bloom in zones 8 and 9 because they lack sufficient winter chilling. There is a vast array of peony colors and forms to choose from.
Most gardeners are familiar with the large, double-flowered peonies.
The single and Japanese bloom types usually perform much better in the South than the doubles do. In addition to the well-known white, pink and magenta flowers, newly available colors include yellow, cream and red. May. Tree peonies bloom a week or two earlier than herbaceous peonies. Early blooming cultivars do best in the South as they have time to bloom before hot weather sets in. They are also less prone to botrytis blight.