Tree and Herbaceous Peonies
(Pronounced pee-ah-NEEE unless you are from the Midwest where it is pronounced pee-OH-nee)
The planting site for peonies should be deeply dug with about three inches of an organic amendment such as Master Nursery® Gold Rush to which has been added Master Nursery ® Master Start (5-20-10) a high phosphorus fertilizer. Use Master Nursery® Master Start at the rate of one pound per 50 square feet or half a cup per bush. Peonies require full sun in the Bay Area in order to bloom well. The planting site should be prepared several days before planting and then allowed to settle before placing the plants.
Herbaceous peonies die to the ground in the fall. Tree (actually shrub) peonies produce flowers on permanent woody branches. Position herbaceous peony roots carefully since planting too deep will prevent them from flowering. The eyes on the stems should be no more than one inch deep in the Bay Area. Set tree peonies so the graft line is three to four inches below the soil surface. Mulch established plants with two to four inches of Master Nursery® Gold Rush or other suitable material.
Herbaceous peonies bloom best where they experience a period of pronounced winter chill. Well grown clumps reach two to four feet tall and as wide or wider. Blossoms range from two inches to as much as 10 inches in diameter depending on the variety.
Tree peonies are deciduous shrubs and will grow slowly to be three to five feet tall and eventually as wide. When mature, they produce very large flowers (10-12 inches in diameter). It may take several years for those peonies to become fully established in the garden. Tree peonies require less winter chill than herbaceous peonies. All peonies will benefit from an application of Master Nursery® Rose and Flower Food applied about Memorial Day and Labor Day.
A recently introduced peony from Monrovia is the Itoh peony (pronounced EE-toe). This is a cross between an herbaceous peony and a tree peony. This cross combines the best traits of both parents: great vigor, large distinctive flowers, strong stems and long lasting blooms. The shrub-like plant is herbaceous in habit, completely dying back over winter.
The Itoh peony has a very large, double blossoms which stand above the lush, dark green, deeply dissected foliage. The flowers have a pleasant, slightly spicy scent and are spectacular cut flowers. An especially vigorous plant, the sturdy flower stems require no staking. Plant the Itoh peony in full sun. They are fast growing to two and one-half to three feet tall and wide and flower in late spring. Follow a regular watering schedule during the first growing season to establish a deep, extensive root system. Remove spent flowers carefully so as not to injure any side buds. For a neat appearance, remove old foliage taking care not to cut into buds at ground level.
Presently available are a large selection of two forms of peonies:
- Herbaceous Peonies – average height of 24 inches in white or pink.
- Itoh Peonies – 18 to 26 inches tall in yellow, orange, and white and white with lavender flecks.
Expect that it will take two to three years for your peonies to become established, but they are worth it and will last a lifetime!