University of Michigan Matthaei Botanical Gardens & Nichols Arboretum student summer intern Zhenzhen Zhang enjoyed the rare opportunity to observe the peony cut flower judging sessions at the American Peony Society annual meeting in Louisville last May 2015. Zhenzhen recounts her experiences at the show.

My name is Zhenzhen Zhang and this summer (2015) I’m working as an intern in the University of Michigan Nichols Arboretum Peony Garden. I have an undergraduate degree in ornamental horticulture and I’m now pursuing a Master of Landscape Architecture in the U-M School of Natural Resources and Environment.
My undergraduate background has given me some knowledge of peonies. Moreover, peonies, especially the tree peony, originated in China.
Dr. David Michener, the curator at Matthaei Botanical Gardens & Nichols Arboretum, invited me to the American Peony Society meeting this May. While there I had the rare opportunity to observe the peony judging process. It was an honor to be an observer of the judging and it provided me a lot of insight into the world of the peony as a cut flower in the U.S.
The grand champion—or “Queen of the Show”—at the APS convention was the variety ‘Salmon Dream’. This variety, pictured below, had a clean coral color and perfect symmetry.
Grand Champion – “Queen of the Show”
So what made this peony the Queen of the Show? Judging of cut peonies depends on several criteria. Before we talk about those criteria, let’s review the six peony bloom forms.
First is the single form. Singles in cultivation may have up to 15 petals (wild form 5 petals), with a saucer shape, pollen-bearing stamens, and functional carpels.
Single form peony
Next is Japanese form. Diagnostic of the Japanese form are staminodes—rudimentary or sterile stamens that do not produce pollen, which means there are transformed stamens in which that original is still recognizable.
Japanese form peony

The third is the anemone form. The stamen transformation has progressed to the point where all visible evidence of stamen origin, except for its yellow color, has disappeared.
Anemone form peony
The next is the bomb form. This form looks like a ball sitting on a plate.
The semi-double form has prominent stamens and a bulking of petalage (one of the segments of the corolla of a flower), an increased number of guard petals, or a guard petals structure which adds visual bulk to the flower.

The last one is double form, in which all stamens and carpels are transformed into petals.
We need to know these forms because they are the basis for classifying peonies. If the exhibitor places his or her peony in the wrong group—for instance mistaking a semi-double for a single—no matter how perfect the peony is, the flower loses any opportunity for an award.
Bomb form peony
Another factor in peony classification is its group—Lactiflora, Hybrid, Suffruticosa, Lutea; Moreover, the color is also considered in the classification, such as white, pink, and red.
Double form peony
Now to the peony judging. What do judges look for?
1. Form
The perfection of form is the most important to the judging process. This means petals must be uniform and symmetrical; Japanese and singles should be properly placed; doubles should have petals symmetrically arranged with edges re-curved with a rosebud center.
Semi-double form peony
Poor form will look ‘relaxed’ or drooping, and sometimes the stamens and staminodes are not firmly held. Cupped varieties should not be cupped to hide the center. Guard petals may have notching and uneven length.
2. Color
The color should be clear, clean, and fresh. Multi-colors should be harmonious. The texture of petals should be silken, with a velvet or satiny sheen.
Symmetrical, uniform.

3. Condition and Grooming
Flowers should be in fully mature and peak condition; fallen pollen indicates they are past prime. Judges also watch for bruised petals and dark spots; there should be no side buds.
Judging only considers the condition of the flower at the moment of judging, and does not take into consideration whether the flower would bloom nicely the following day, or whether it bloomed perfectly the day before.
Exhibitors came from all over the United States. Peonies from warmer climates  bloom earlier, while peonies from colder climates may bloom later. In order to make their own peonies show well at the judging, exhibitors employed methods to keep or force peonies to open. Delivery is also a time when peonies might be damaged. So attaining the best form, shape, and condition is challenging. What’s seen at the judging represents an entire year of preparation. They all deserve a reward!

Drooping petals
You can see some flowers in 
this white group are not pure 
white, so they are not good ones

A sample of Carol Adelman’s peonies. Carol is owner
of Adelman’s Peony Gardens in Oregon.
Examples of peonies belonging to another exhibitor.

The right one is not mature, so not blooming well.

Zhenzhen Zhang, from China, recently completed her first year in the Master of Landscape Architecture in the U-M School of Natural Resources and Environment. She is working as an intern in the horticulture department, in particular in the Nichols Arboretum Peony Garden. Zhenzhen is interested in ecological design and development.