Three Kinds of Peonies

  • Post published:10/20/2012
  • Post comments:2 Comments
Pink Herbaceous Peony

In the past I have written about two kinds of peonies, the indomitable herbaceous peony that needs to be cut back in the fall, and the ancient tree peony that originated in China and blooms on woody stems that are more shrubby than tree-like. Both are extremely hardy with beautiful spring flowers in a variety of forms including the classic bomb with its very heavy blossom.

Many see that the drawback of the herbaceous peonies, especially those with very heavy blossoms, is the way hard spring rains beat those blossoms down. This has led to the rise of metal peony rings to support the blossoms, and the practice of planting them at the edge of a low stone wall so that the rains will only make the soaked blossoms bend into the air, and not into the mud.

The drawback to tree peonies is that they grow to a substantial size, four feet tall and wide or more. This is a magnificent sight when a mature plant is covered with fifty blossoms, held high even in the rain. However, they do have a very short bloom period which means you have a large plant that may not provide much interest in a small garden for a good part of the year.

Now there is a third type of peony called the Itoh or intersectional peony, a cross between the herbaceous and tree peony that combines the best of both worlds. Itoh peonies bloom on strong stems that do not need staking or other supports, and a mature plant will produce more than one bloom on a stem making for a longer bloom season. They are also small enough to easily fit in most gardens.

The Itoh peonies are named for their hybridizer, Toichi Itoh, who developed them in the 1940s. They are not commonly grown because they are expensive. Although the price has come down substantially since they were first introduced almost all of these hybrids cost $100 or more. I should note that many tree peonies will also cost nearly as much.

Clearly, including tree peonies and Itoh peonies in your spring garden requires an investment. After all, many herbaceous peonies can cost as little as ten dollars.

I started planting herbaceous when we first moved to the end of the road in 1980. Although peonies don’t like to be moved, they will survive a move that is carefully handled.  Fall is the traditional time to plant, or move peonies.  Because they are such long lived plants special care should be taken when planting.

Dig a large hole, 12 to 18 inches deep and enrich that soil with compost, well rotted manure and some bone meal or rock phosphate. Peonies are not terribly fussy. They don’t mind slightly acid soil, but they do need good drainage and a sunny location.

The trickiest part of planting peonies is not to plant them too deeply.  The crown should only be one or two inches at the most, below the surface of the soil. Deeper planting will not harm the plant, but it will not bloom. If you have a non-blooming peony it should be dug up and replanted at the proper depth. Whenever gardeners have complained to me about a non-blooming herbaceous peony the problem has been too-deep planting.

If you must move a peony or want to divide it, first cut the foliage back to the ground then dig it up very carefully. The roots are large, deep and brittle. It will not necessarily damage the plant if you loose some of the root. If you buy bare-root peonies you will see that the roots have been trimmed. It can be quite a surprise to see how large the roots of an established plant are. Itoh peonies should be planted the same way.

If you want to divide the root, look for the little eyes on the crown. Use a sharp tool to cut the fleshy root and give each piece at least three eyes. This will guarantee flowers next spring.

After planting and after the ground has frozen, it is a good idea to mulch peonies for the first year.

Guan Yin Mian tree peony

Tree peonies do not get cut down to the ground in the fall. They have a woody, shrubby structure. When you plant tree peonies they do need to be planted so that the graft point is four inches below the surface of the soil. In every other way they have the same needs as herbaceous peonies.

Peonies are very hardy and will live for decades with little care. Even so, general practice recommends spring fertilizing with compost, which is what I do after weeding in the spring, or other organic fertilizer.

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Acidanthera

Peonies are important spring bloomers, following many of the spring bulbs. Last week I asked my readers if they had a favorite bulb. Margo Culley emailed me to praise what I called Acidanthera and what she calls Abyssinian glad. Taxonomists are always changing names, but either way, this tender bulb does send up a lovely, and fragrant, flower. It looks nothing like the gladiolas that are familiar to most of us. It has slim upright foliage and graceful star shaped white flowers with a deep red heart.

I first saw this lovely flower on the Bridge of Flowers and bought my bulbs at Shelburne Farm and Garden this spring.  It is a tender bulb and cannot overwinter in our climate. You can dig them up, or treat them as annuals. They are not expensive. Culley says they can be hard to find but there are online sources. I’m glad I just had to nip down to Shelburne Falls. Thank you, Margo, for letting us know about this beautiful flower.

Between the Rows  October 13, 2012

This Post Has 2 Comments

  1. Jason

    I have the herbaceous peonies only. I fear I grow them in too much shade because after blooming they tend to get a bad case of powdery mildew. I love the Acidanthera!

  2. Pat

    Jason – I think you are right. More sun might be the answer to powdery mildew. The acidanthera is a great plant!

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