Extension Communications
3614 Administrative Services Building
Ames, Iowa 50011-3614
(515) 294-9915
4/15/02
Contacts:
Cindy Haynes, Horticulture Extension, (515) 294-4006, chaynes@iastate.edu
Jean McGuire, Continuing Education and Communication Services, (515) 294-7033,
jmcguire@iastate.edu
Yard and Garden Column for the Week Beginning April 19, 2002
An Iowa Favorite: Petals from the Orient
By Cindy Haynes
Consumer Horticulture Extension
Iowa State University
and
Jessie Lowrie
Horticulture Student
Iowa State University
Peonies have a long garden history. They have been grown for centuries
in China, where the plants are native. Herbaceous peonies have also been
grown and appreciated in the United States for more than 100 years. The
pioneers transported these prized flowers in their covered wagons as they
settled in the West. Today, peonies are prized garden perennials in Iowa
for their beautiful blooms around Memorial Day.
Types
There are several types of garden peonies. The expensive fern-leaf and
tree type peonies are popular because of their unique foliage, growth
habit and flower color. However, the long-lived herbaceous peony, common
to Iowa farmsteads, is the most durable and popular in the Midwest. Herbaceous
peonies have single, semi-double, Japanese or anemone type blooms in red,
pink, white, cream, or purple colors. The blooms last for two to three
weeks in spring, depending on weather conditions. Since their bloom time
often coincides with Memorial Day, peonies are often found in cemeteries.
Site Requirements
Peonies perform best in full sun with at least six hours of direct sun
per day. Peonies also like plenty of room; ideally with three to four
feet between plants. Overcrowding can cause poor growth and below average
blooms.
Peonies are tolerant of diverse soils but perform best in moist, well-drained soils with plenty of organic matter. Heavy clay or soggy soils that are not amended can lead to poor growth and slow establishment.
Planting
Peonies can be purchased as potted or bare root plants. Both types should
not be planted too deeply. The buds or "eyes" should be one
to two inches below the soil surface. The crown of the plant, where the
eyes are located, should be just below soil level. Deep planting will
produce plenty of foliage but few blooms.
Potted peonies are best planted in spring or early fall. Carefully remove potted plants from their containers and place in the garden at the same depth they were growing in the container. Try to keep the soil ball intact and water well after planting.
Late summer is the best time for planting bare-root peonies. Spring plantings are also successful but do not bloom well the first year. After digging a hole, position the plant in the center of the hole and gently spread out the plant's roots before backfilling with soil. Water plants well after planting.
Timing of planting can be important late in the season. Peonies need at least one month of warm soils for root growth and establishment before winter. Late fall plantings may not successfully overwinter if roots do not have time to establish and prepare for dormancy.
Dividing
Peonies do not require regular division like some other perennials. In
fact, some plants can remain undisturbed in the same spot for decades.
However, if flower production declines or you want to increase the number
of plants in the garden, peony division is easy and highly successful.
In late August and September as the foliage begins to yellow, carefully
dig up the entire plant. Using a sharp knife separate the thick roots
into large clumps. Each clump or division should have at least three to
five"eyes" or buds. Replant immediately and water. Give extra
divisions to friends or neighbors for them to enjoy in their garden.
Maintenance
Deadheading, or removing spent blooms, is not required but will improve
the plants' appearance. Plants can also be encouraged to produce larger
blossoms by removing the lower or auxiliary buds along each bloom stalk
prior to the terminal bud opening. However, creating large, heavy flowers
often means providing additional support with stakes due to the weight
of the blooms. Staking floppy peony blooms is a common gardening chore,
especially after a heavy rainfall.
At the end of the growing season, the dead peony foliage should be removed from the area. Many peonies have problems with leaf blotch and it is essential to remove any affected foliage to prevent infection next year. Infected foliage should not be composted.
Peonies easily fill the unbearable lapse of landscape blooms between spring bulbs and summer annuals. So, plant a peony and enjoy their blooms for many years in your garden!
Why won't my peonies bloom?
Many people mistakenly think that ants are necessary for peonies to bloom.
While peony buds do supply nectar to ants and other insect visitors, they
are not required for blooms to open. Instead, regular bloom production
is dependent on the factors listed below.
Planting depth - Peonies should be planted with the buds one to two inches below the soil surface. Any deeper and the plant produces lots of foliage, but few flowers.
Disturbance - Recently planted or divided peonies may not bloom until their second or third year.
Fertilizer - Plants heavily fertilized with high amounts of nitrogen will also produce more foliage than flowers.
Light - Peonies receiving less than six hours of direct sunlight per day do not bloom well.
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ml: isugarden
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