The peony plant, from the genus Paeonia, is a hardy perennial that is low maintenance once it becomes established. Peony plants are available in many colors and bloom sizes, making them a versatile accent to flower gardens. The plants bloom in late spring to early summer and provide green foliage through the rest of the growing season.
Peonies are a perennial plant available in three types; tree, herbaceous, and intersectional. Herbaceous and intersectional types of peonies are hardy in Zones 2 through 8, while tree types will grow in Zones 4 to 9 with winter protection. Peony plants grow best in full to partial sun where they receive at least 6 to 8 hours of light per day. The plants are drought tolerant and can grow in most soil types that are well drained.
Pests and Diseases
Peonies rarely show disease or have pest problems. Ants are often seen on the flowers and buds, but will not harm the plant. Ants eat the sweet plant secretions and have no effect on bud opening. Cut flowers should be cut prior to the flowers opening to prevent ants from clinging to them. Stems that are rotted at the ground level are due likely to the fungal diseases Botrytis or Phytophthora. The cause of fungal disease in peonies is cold, wet weather. Remove and destroy all infected areas of the plant to prevent the disease from spreading.
How to Plant
Peony plants do best when planted in the fall to allow the roots to start sending shoots. The majority of root growth in peony plants occurs in the fall season. Tree peonies are planted as a graft. Dig a hole that is 4 to 5 inches deeper than the graft location and place the tree peony in the hole. Cover with dirt, making sure the graft is under ground. Herbaceous and intersectional are grown from tuber plants. Make sure the tuber has 3 to 5 buds present on the plant prior to planting. Dig a hole that is 1 or 2 inches deeper that the bud location, set the tuber in, and cover making sure the buds are underground. Set peony plants 2 feet or more apart from each other when planting Water after planting and apply a layer of mulch that is 1 to 2 inches deep.
Care and Maintenance
Peony plants require one application of fertilizer in the spring when the shoots are approximately 3 to 4 inches in height. Use a fertilizer that is 10-10-10 or 5-10-5 and water thoroughly after application. Some peony varieties require support structures to prevent plant drooping. Place a support cage around the plants or set 2 to 4 poles around the plant with string wrapped around the circumference to support the plant.
Separation and Moving
Propagate herbaceous and intersectional peony plants by separating the tubers of the main plant. Dig up the entire plant in the fall and pull apart the root tuber sections making sure each has at least 3 to 5 buds present. Plant the divided sections according to the How to Plant section. Divide peony plants every 10 to 15 years or if they become closely set together. Tree peony plants can only be propagated through grafting.