Peonies in the Ripley Garden

Everyone adores peonies – it is one of those plants, along with tulips and lilacs, that cry out “Spring is here!”  

The peony most people are familiar with is the herbaceous peony or Paeonia lactiflora. These plants produce fragrant blossoms in all shades of white to the deepest red, with petals counts ranging from just a single row to solid pompoms.   ‘Herbaceous peony’ means the plant dies back entirely during the winter and re- appears in the spring.  Native to areas like Tibet, Northern China, and Siberia, it makes sense they survive down to Plant Hardiness Zone 4, but are not happy in zones warmer than 8.  This type of peony is the last to bloom for me in the Ripley Garden;let me introduce you to a few other members of the Paeonia family I grow.

The first to bloom for me is a woodland species, Paeonia japonica.  Yes, you read that right, there are peonies that thrive in the shade. This delicate Japanese native is just a foot or two high, with the most delicate single white fleeting flowers lasting just a couple of days!  If the seed pods are left to develop, you will be rewarded with amazing indigo and scarlet seedpods in the fall.    

The next to bloom for me is the Fernleaf peony, Paeonia tenuifolia. This enchantress is native to the Caucasus mountain range in Georgia (former USSR) and is grown as much for its foliage as its flower.  I so remember pictures posted by my friend Panayoti Kelaidis of ACRES of 2-foot tall ferny mounds dotted with brilliant red flowers covering open hillsides in Georgia.  These plants are easy to grow in full sun and rich loamy soils, but patience is needed to get some bulk to them.   

Next to bloom in the Ripley Garden are the Tree peonies or Paeonia  suffruticosa. Known as Mudan or Moutan in their native China, these are the showboats of all the peonies.  There is no missing these plants when in bloom.  Massive 6-8″ flouncy flowers are so heavy they can split the 5-6′ tall and wide plant open.  Support is often needed to shore up these  enormous flowers; a heavy rain or high winds may shorten their display.   

A Tree peony does not quite live up to “tree” stature, but unlike their herbaceous cousins they do get woody stems that are present year-round.  I have two tree peonies in the Ripley Garden. The first to bloom is usually Paeonia ‘Anna Marie’ with her single orchid lavender flowers with deep raspberry basal flare. 

The Flamboyantly fabulous semi-double ‘Godaishu’, typically blooms a week later.  This ancient Japanese variety is pure white with a mass of golden stamens peeking out from a ruff of petals.  

Tree peonies are happiest in cooler climates with some being hardy in Zone 3, but easily grown from Zones 4 to 8.  These are large plants, requiring 5 to 6 feet of ground space in full sun to lightly shaded areas.  Protection from hot afternoon sun will extend the bloom time.   

The next type of Peony to bloom in the Ripley Garden results from crossing the herbaceous lactiflora peony with a tree peony which yields an intersectional hybrid.  This group of peonies is often referred to as “Itoh” peonies after Toichi Itoh, the first person to successfully make this cross in the late 1940’s.  

Hybrids display the best traits of their parents.  They are more heat– tolerant, have a mainly herbaceous habit, and produce flowers in a wide color range including yellows and coppers. Two Intersectional peonies are grown in the Ripley Garden.  The first to bloom is ‘Hillary,’ a semi-double beauty whose color is a coppery pink, that matches our native Columbine (Aquilegia canadensis) both in bloom time and color.   

The second form, ‘Bartzella,’ a glorious lemon-yellow semi-double fragrant beauty, is probably the most famous of the group.  Both ‘Hillary’ and ‘Bartzella’ were bred by Roger Anderson of Wisconsin.  Anderson first bred ‘Bartzella’ in 1986.  When they were first available for sale in the early 1990’s, a small division cost close to $1,000.  Now thanks to micropropagation, they are readily available at reasonable prices.  

The last of the peonies to bloom in the Ripley Garden are the herbaceous lactiflora peonies I described earlier.  These are the common herbaceous peonies we all adore.  Most all are delightfully fragrant and make a great cut flower.   

These bloom best in full sun and rich, well-drained soil.  Common reason for plants not blooming include a lack of not enough sunlight or being planted too deeply. The crown of the plant needs to be right at the soil line, not submerged.  Dividing or moving a plant will set it back slightly until it gets re–established.  

The one lactiflora peony in the Ripley Garden is ‘Chiffon Clouds,’ a single flowered form in shades of the softest salmon changing to the palest pink.  

If the Ripley Garden were larger, I know I would find room for more peonies since there are thousands of gorgeous species and hybrids available.  All of them are exceptionally long– lived and just get more glorious with age.  Spring and fall are the best planting times for peonies.  Remember not to plant them too deep and they will give you decades of joy.  

Janet Draper, Horticulturist
Smithsonian Gardens