Learning to Grow: Peonies signal summer’s start

For most people, Memorial Day marks the unofficial start of summer. For me, the season begins when the peonies bloom. The spring ephemerals have come and gone by now, and I am ready to trade the decidedly tattered and world-weary tulips and daffodils for the lilacs perfuming the air around every corner, the green grass and the peonies. Though their bloom period is short – just about two weeks – these are the days that really signal the end of a chilly, damp spring and the beginning of a season filled with lush blossoms and sunshine.

Peonies are often classified according to their varying flower types – single, Japanese, semi-double, fully double and bomb. Both the single and Japanese varieties have at least one row of large cupped petals encircling bright yellow stamens in the center. Semi-double flowers are a bit fluffier than the single or Japanese types, featuring multiple rows of petals surrounding a still visible yellow center.

But the fully double and bomb peonies are remarkable for the rows and rows of petals that completely cover over the centers of the flowers, with the bomb type notable for a flat ring of petals around the outside, and a compact “bomb” of petals forming a spherical mass on the inside.

In addition to the different bloom types, peonies exist in herbaceous, tree, and intersectional (a hybrid of herbaceous and tree) forms. Herbaceous peonies have soft stems and die back to the ground every fall, sending up new growth in spring, while tree peonies have a woody stem and only lose their leaves over the winter.

The intersectional variety is a hybrid of the other two, dying back to the ground each fall, but with flowers and leaves that more closely resemble those of the tree peony.

Peonies are lovely planted en masse or as a focal point in perennial beds and borders, and planting a long row of a single type will create a charming little hedge of blooms. When choosing and planting them, it is important to note that unlike many perennials, peonies do not require regular division to keep them healthy and blooming.

In fact, not much maintenance is needed to sustain them – the plants actually object to disturbances – so if you, like me, are inclined to frequent moving of the “furniture” in your outdoor rooms, peonies will offer a nice opportunity to tackle some of your commitment issues. (Baby steps!) Just site them in a sunny spot with good drainage, add a little organic matter, and leave them to their devices. When they reach about one foot in height, you may want to cage them to prevent any heavy flowers from drooping.

Peonies are tough, cold-hardy plants, and with a reputation for surviving for 50-100 years, they may well outlive you! Fall is the best time to plant, giving roots a chance to become established before winter, so just use the next few weeks to watch their thrilling performance, drink in their fragrance and take notes. And, if you’re feeling charitable, grab a copy of your will. And a pen. 

• Sarah Marcheschi is a University of Illinois Extension master gardener for Kane County. Call the extension office at 630-584-6166 for more information.