“Asters, like prophets, are without honor in their own country,” said Louise Wilder Beebe. Known as “Michaelmas Daisies” because they bloom around St. Michaelmas Day on September 29, asters are held in high esteem by English and other European gardeners, while we in the United States distain them as common weeds. They have to compete with the vigorously promoted Asian chrysanthemums that are available at the grocery store, the hardware store, big-box stores, roadside stands, and the pumpkin farm, and asters come out a distant second.
My house in September
Our native asters, however, are the last act in our vast prairie drama and their purple, lavender, azure, mauve, and white palette is dazzling. Aster cultivars, such as ‘Purple Dome’, ‘Alma Potschke’, and ‘October Skies’ are readily available at garden centers, but you will have to look further for the equally beautiful straight species asters. They are available at native plant nurseries and through native plant catalogs or, even better, from friends.
Five asters dominate my prairie garden in fall:
Smooth Blue Aster
Sky Blue Aster
New England Aster
Smooth Blue Aster (Symphyotrichum laeve) is lavender, not blue, but it does have smooth leaves and stems. Its dark green leaves clasp the stems, a characteristic that makes this plant easy to identify. In the garden it grows up to 4’ tall in a narrow, upright fashion, but grows only 1-2’ in the densely crowded prairie.
The colorful autumn leaves of Foxglove Beardtongue (Penstemon digitalis)contrast beautifully with Smooth Blue Aster.
I planted Sky Blue Aster in my garden many years ago, but it disappeared and I’ve never replaced it. This photo was taken at Morton Arboretum where it pairs up beautifully with the autumn copper-colored Little Bluestem. Sky Blue Aster used to have a beautiful scientific name–Aster azureus. It has now been re-named Symphyotrichum ooleniangiense.
Sky Blue Aster in June’s garden with Prairie Dropseed 10/3/10. Open panicles of long-stalked, sky blue daisies bloom at the tops of 2-4’ tall stalks. In the wild they are found in dry prairie remnants and sandy Black Oak savannas in bloom from late August to early November.
The most colorful and best known of the species asters is New England Aster (Symphyotrichum novae-angliae), with intense purple or occasionally rosy flowers that bloom from early September to the end of October. An upright, multi-stemmed plant, it grows 2-4’ tall on leafy stems. It is a common resident of wet and mesic prairies, calcareous fens, moist meadows, and conversely, dry pastures, roadsides, and railroad tracks. It grows well in clay soils.
Heath Aster (Symphyotrichum ericoides), named for its narrow heath-like leaves, grows 2 1/2 -3’ tall and around; its elongated clusters of tiny, white stars begin to bloom mid-September and carry on through mid-October. Common in remnants of dry prairie and along railroad rights-of-way, it can also be found in moister prairies, says Plants of the Chicago Region.
Heath Aster and New England Aster growing together in my garden.
Aromatic Aster (Symphyotrichum oblongifolium) forms a 2-3’ soft, billowing mound covered with 1 1/2 “ daisies with pointed, deep violet rays and yellow discs (turning to burgundy with age) that bloom over a long period of time, from mid-September through the end of October. Indigenous to hill prairies, it is rare in the wild; nevertheless it flourishes in my garden, spreading quickly by rhizomes and seeds. It does, however, need a well-drained situation–it won’t survive in clay soil. Combine it with the now copper-colored Little Bluestem.
Cut back tall asters by one-half at the end of June and again at the end of July to make them branch out and inhibit their tall growth somewhat.
A melange of asters grow along my front sidewalk–New England, Smooth Blue, Heath, and Aromatic. The copper Little Blue Stem is a stunning contrast to the purple, azure, and white asters.
Smooth Blue, Heath, and Aromatic Aster on my west parkway.
In addition to being stunningly beautiful, asters are butterfly magnets–
Two Monarchs on New England Aster
Even better–I have records of a Buckeye migrating on 21 October 2011 and 8 October 2013, both times spending the day in the Aromatic Aster in the front yard.