Second Week in September
Up to now most of the plants that have been in bloom along our roadsides have been Eurasian weeds that have crowded out our native plants. But in late summer and fall, our indigenous plants come into their own and decorate our roadsides and fields.
The flamboyant, iridescent golden chenille plumes of Canada Goldenrod (Solidago canadensis), more common west of Lake Michigan, and Tall Goldenrod (Solidago altissima), more common east of the lake, are dazzling along our roadsides now. Our most common goldenrods, they grow abundantly in fields, roadsides, disturbed prairies, pastures, and disturbed open woods. Gorgeous, but too aggressive for a garden.
Goldenrod has been wrongly accused of causing hay fever, but Common Ragweed and Giant Ragweed (Ambrosia artemisifolia and Ambrosia trifida), which disburse their pollen through the air at the same time goldenrod is in bloom, are the real culprits. Plants with showy flowers, such as goldenrod, are insect pollinated–their pollen does not blow through the air; while plants with inconspicuous blossoms, such as grasses and ragweed, are wind pollinated.
This is the September Prairie at Christ the Lord Lutheran Church in Elgin with Canada Goldenrod at the back and Showy Goldenrod (Solidago speciosa) and Stiff Goldenrod (Solidago rigida) along with Rough Blazing Star (Liatris aspera) and Heath Aster (Aster ericoides) in the foreground
The little tufted golden daisies of Stiff Goldenrod are arranged in flat corymb clusters at the top of 1-5’ stems that reflect the flat prairie.
Common in dry to moist prairies, Stiff Goldenrod also works well in the garden. Plant it at the back of a south-facing border; use it to accent a built object–stone walls are always great. It begins to bloom in late August and continues through September. It’s especially attractive to Painted Lady butterflies, in my observances.
Showy Goldenrod has an entirely different look. Its even smaller golden daisies are arranged in a cylindrical plume. It is frequent in sandy Black Oak savannas, but it will also grow in dry or mesic prairies. It makes a good subject for the home garden, as well; it grows 1-3’ tall–plant it in the middle of the border. It’s an aggressive seeder, but I welcome all new plants. It, too, begins to bloom late August and continues through September.
In September, 2008, the stars aligned just right, and Showy Goldenrod and Rough Blazing Star bloomed concurrently in our church prairie, an absolutely stunning combination! (In most years, Rough Blazing Star finishes bloom just before Showy Goldenrod begins.) In nature, both grow together in sandy Black Oak savannas and dry prairie remnants. I urge you to plant them together in your garden within a matrix of Little Bluestem.
Rough Blazing Star (Liatris aspera) is not as well known as its earlier blooming cousin, Prairie Blazing Star (Liatris pycnostachya), but it is equally gorgeous. Its rose-purple flower tufts spill out of large cups arranged in an open fashion alternately around the 1-3’ stem in August and September. Like all Blazing Stars, the flower spikes start to bloom from the top down instead of from the bottom up as most other spike flowers do.
This photograph was taken early in September in 2009 at the Morton Arboretum. Rough Blazing Star is planted at the top of a bank near the edge of a pond within a matrix of Little Bluestem in its fall/winter copper dress–a ravishing pairing!
Another butterfly magnet, I’ve noticed many Sulfurs enjoying the nectar.
Heath Aster (Aster ericoides), so-named because its tiny, stiff, narrow leaves resemble those of Heath, has also started its fall bloom. Its diminutive, 1/4” diameter, gold-centered stars form dense plumes at the top of stiff 1-3’ stems in September through early October. It makes dense patches in prairie and garden through its creeping rhizomes.
Don’t confuse it with the weedy Hairy Aster (Aster pilosus) found in old fields, pastures, waysides, and degraded prairies. Hairy Aster is larger than Heath Aster–up to 4’ tall–with larger flowers, and well, hairy.
These plants are all members of the Sunflower family. To learn more, check out The Sunflower Family in the Upper Midwest by Thomas M. Antonio, a former Research Botanist & Suzanne Masi, a current Research Botanist, both at the Chicago Botanic Garden.
Pick up the current September-October issue of Chicagoland Gardening. An article called Chicagoland Natives, Late Summer Stars, on page 24, features a photo of the front and side of my Sears bungalow surrounded by clusters native asters taken last September. The article was written by April Anderson, the Naturalist at Elgin’s Hawthorn Hills Nature Center.