A dearly loved Perennial
Common Name: garden or Chinese peony
Botanical Name: Paeonia lactiflora
Form: upright vase
Plant Type: herbaceous perennial, tuberous roots
Mature Size: 12” to 36” depending on variety
Origin: Europe, Asia, North America
Hardiness Zone: 2 to 8
Foliage: green, compound, lobed, alternate, fall colour
Flowers: May, June depending on variety, up to 10” across, all colours except blue, many flower types available
Fruit: aggregate clusters, follicles with black seeds
Exposure: sun, part shade
Uses: garden borders, perennial beds, cut flower, background plant
Propagation: division, seeds
Pruning: deadhead spent flowers
Problems: botrytis, peony leaf blotch
Comments: Garden/Chinese peonies are adored for their impressive, huge, globe-shaped fragrant blossoms that arise from rounded plants with handsome green foliage. Their flowering period only lasts a couple of weeks, but can be extended if you plant early, mid, and late flowering varieties.
There are numerous species of peonies, including herbaceous garden peonies, Paeonia lactiflora, that die down in fall and tree peonies, Paeonia suffruticosa, that are considered deciduous shrubs due to their woody stems. The Itoh (or Intersectional) is a cross between herbaceous and tree peonies. Their foliage resembles tree peonies, however, they are herbaceous and non-woody. All peony types boast gorgeous large blossoms.
Most peonies are fragrant with cup-shaped petals; however, the number, type and arrangement of petals differ depending on the flower type: single, Japanese, anemone, semi-double, bomb and double. They do well in sun and partial shade and are tolerant of many soil types with good drainage. They will become leggy with drooping flower stems in too much shade - if they flower at all.
Dividing garden peonies when flowering ebbs, which occurs after about 10 years. Divide them in the autumn after leaves yellow. Use a sharp knife to cut into the tubers, leaving 3 to 5 eyes (buds) on each section. Allow them to callous over for a couple of days, then replant. Bury the tubers so the eyes are no deeper than one inch. They will not flower if they are planted too deep. Space plants 3 feet apart and mix in some compost and a small handful of bonemeal.
Mulching Peonies: Although peonies are quite hardy, if you live in USDA growing zones from 2 to 5, it’s a good idea to cover them in fall with a winter mulch of fallen leaves. Just don’t forget to remove the mulch in spring. For warmer areas, a winter mulch is not needed, however no matter what climate you live in, peonies benefit greatly from a mulch (as most plants do).
Deadheading & Fall Clean-up: Cut off spent blossoms to prevent seed production and to tidy the plants. Cut off foliage once it yellows in autumn to discourage overwintering diseases.
Botrytis Blight: Peonies are easy to grow as they don’t have many insects or diseases; however, they do suffer from botrytis blight and leaf blotch (peony measles). Botrytis blight (gray mold) attacks many plants when there is extended periods of rain and high humidity. It attacks the tender growth especially the blossoms. Symptoms include flower buds that fail to open. They become mushy and covered with grey mold. Brown lesions and grey spores also appear stems and leaves. To control this disease, collect and destroy all contaminated plant parts including those on the ground and on the plant. Cut off infected plant parts and disinfect pruners after each cut. Mix 1 part disinfecting Pine-sol or Lysol, to 1 part water. Use a spray bottle for convenience.
Peony Leaf Blotch: Another common peony disease is peony leaf blotch, also known as peony measles. Click on Peony Blotch/Measles for more information.
Ants: Don’t worry if you see ants on peony buds as they protect the blossoms from predators. In exchange, they feed on the peony’s nectar, which does not hurt the plant. For information on tree peonies, click on Tree Peonies