The peonies you plant this year can be enjoyed for generations
Did you know you can grow an heirloom plant for your descendants? We often speak of heirloom varieties of open-pollinated vegetables and flowers, but those may be changed over time because of their susceptibility to pollination by other plants. The heirloom I’m referring to is a peony, a very long-lived herbaceous plant. Peonies can grow and produce blossoms for at least 100 years, and it will be the same flower and foliage at the end as it was at the beginning.
Whenever they’re dug, another may arise from a bit of root left in the ground, a bonus. Peonies should not be planted so that the eyes (on the root crown) are deeper than two inches. If they are planted deeper, they probably won’t bloom, and those voluptuous, fragrant blossoms are the main reason we love peonies. The foliage turns pretty in fall, too, just before you should cut the foliage to the ground so that you don’t overwinter a disease.
Blossoms are often heavy, and weather can wreak havoc on these plants. Some folks buy costly peony supports, some use tomato cages that have been spray-painted green, and others just lay a square of chicken wire fence over the peony roots. As the plant grows through the chicken wire fencing, it raises the wire support. holding the entire plant together.
You can buy early, mid-season and late peonies, extending the bloom cycle for two months or a little longer. Fern-leaf peonies (Paeonia tenuifolia) are among the earliest to blossom, long before Memorial Day. The provenance of my fern-leafed peony was from Japan to Notus, where I bought it from a grower several years ago. When a shrub in my yard threatened to overtake it, a friend dug it and moved it for me. It was sufficiently large to be divided it so she could have a special plant in payment for her work.
My fern-leafed peony has single blossoms, crimson with a gold center, but doubles are available as well. Peony blossoms as cut flowers last about a week indoors, but you can extend their life with dehydration or refrigeration. To refrigerate them, cut stems about six inches long when buds are beginning to show color, and put them in a sealable container lined with a single thickness of wet paper towel. Store this in the hydrator drawer of the refrigerator for up to two months. To refresh blossom pick off the green sepals from the base (protecting petals), cut off stem and put bud in a bowl of warm water. It should be floating open by the next day.
To dehydrate blossoms, cut fairly long stems, strip the foliage off, and tie the stems together. Hang them upside down in a dark closet. In our low humidity climate, they should be dry within a week or ten days. They’ll dry best if you cut the stems before the outer petals begin curving backwards, according to a friend.
Peonies require a modest amount of water, little fertilizer, and full sun for at least six hours each day. Fertilizer should be low in nitrogen, and richer in terms of phosphorus and potassium, something like 5-10-5. Nitrogen rich fertilizer will produce lush foliage but few, if any, blossoms. Fertilize either after first fall frost after you cut foliage to the ground (do not compost this foliage, lest you spread disease) or in early spring.
Removal of foliage in autumn is recommended to avoid botrytis infection and dispersal, a disease common in peonies. Another common disease is leaf wilt, a late blight. Botrytis symptoms are small brown flower buds that do not open and some blackened foliage. Anti-fungal sprays may correct the problem, but be sure the product you use is rated for peonies and correctly applied. Leaf wilt is also controlled by pulling leaves and stems away from the plant, carefully removing sclerotia (tiny globes inside stems) that can spread the infection.
Tree peonies should NOT be cut back in autumn, but Itoh peonies, a cross between the tree and herbaceous peonies should be cut back to the ground. Following that procedure, mulch for winter.
Herbaceous peonies range in color from shades of red to white, including pink of course. Tree peonies and the Itoh or intersectional crosses expand the peony color availability to include yellow.
Ants are often observed on peony plants when they’re in bud. The plant exudes sweet nectar near the buds that the ants love, and in their zeal to protect that source, they protect the plant from bud-damaging insects.
Send garden questions to melauter@earthlink.net or Gardening, The Statesman, P.O. Box 40, Boise, ID 83707.
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Find the list online at IdahoStatesman.com/ gardening. There are several classes this weekend. Know of a free class or gardening event we should add to the list? Email Michelle Jenkins at calendar@ idahostatesman.com.
This story was originally published February 22, 2017 at 3:03 PM with the headline "The peonies you plant this year can be enjoyed for generations."