Monthly Archives: October 2024

Aromatic Aster

Posted on by Brad Guhr

One of my favorite prairie wildflower species has to be aromatic aster (Symphyotrichum oblongifolium). Aromatic asters are hardy, drought-tolerant forbs that bloom toward the end of the growing season. Their leaves have an herbal scent when crushed. Aster species are host plants for caterpillars of butterflies including painted ladies, pearl crescents, and silvery checkerspots as well as many species of moths. In the late summer and fall, aromatic aster flowers delight the human need for color and provide nectar for many insects, most notably, butterflies, bees, wasps, flies and beetles.

Aromatic aster var. ‘Raydon’s Favorite’

According to Mike Haddock at Kansas Wildflowers and Grasses, aromatic aster is found across almost the entire state of Kansas on dry, open prairies. In our Dyck Arboretum reconstructed prairie, aromatic aster (seed collected from the Smoky Hills ~30 miles north of Hesston) is just about finished flowering. Its purple hues popped a couple of weeks ago among the reddish-brown colors of senescing warm-season grasses.

A Star in the Prairie Garden

In our native plant gardens, aromatic aster is the star of a show that we have been looking forward to all growing season. Aromatic aster fills garden spaces between other plants nicely where its dense, low 1′-2′ foliage crowds out weeds and lends above-ground support to neighboring plants. But its late-season flowers are the main reason that this species is a dominant part of our featured Butterfly Garden.

Educational signage in our Dyck Arboretum Butterfly Garden bed (line drawings by Lorna Harder)

While I enjoy observing all prairie flowers throughout the growing season and the pollinators they attract, aromatic asters just seem to take the human entertainment value to a higher level. Given the high number of flowers on each plant and the lack of anything else blooming this time of the year, this species usually seems to put on the greatest show of the year as it plays host to a busy array of insect pollinators.

The two varieties of aromatic aster in our Butterfly Garden are ‘October Skies’ and ‘Raydon’s Favorite’. They bloom at different times and in nice succession for a long season of attracting pollinators. I seem to usually observe the former blooming from late September to mid October and the latter from mid October to early November.

Comparison of aromatic aster varieties ‘Raydon’s Favorite’ on left and ‘October Skies’ on right (Photo by Janelle Flory Schrock)

Whether I’m walking with elementary schoolers, college students or retired master gardeners, this Butterfly Garden spot on a sunny afternoon is always a regular stop. The flowering spectacle by aromatic aster in this time of the year is one of my favorite flower/pollinator interactions in the prairie garden.

When trying to capture the jaw-dropping wow factor of a landscape scene like the Flint Hills or a Kansas sunset, a photo or video never conveys the inspiring scene I want. Nevertheless, here is a video of the super busy pollinator scene I witnessed yesterday (10/22/24).

13 Butterfly Species Observed

The butterflies I observed nectaring on the flowers of aromatic aster var. ‘Raydon’s Favorite’ yesterday included the following species: checkered white, sachem, common checkered skipper, fiery skipper, dainty sulphur, clouded sulphur, orange sulphur, eastern tailed blue, common buckeye, monarch, pearl crescent, Melissa blue, and American lady (not all species were visible in the video). Various species of bees (audibly busy), flies, beetles and moths were also abundant.

Stop by and see our Butterfly Garden before the aromatic aster finishes its show in the next week or two. Better yet, add different varieties of aromatic aster to a sunny spot in your landscape where you can enjoy a similar show for years to come.

For a broader review of asters in general, see my colleague’s great past posts, Asters: Autumn’s Crescendo and All About Asters.

Think Pink

Posted on by Katie Schmidt

Muhly grass is in its prime this time of year, and all our regular visitors are asking about it. This native grass is unforgettable once you see it in bloom, and we are lucky to have multiple types growing on our grounds. Read on to find out which species is right for you!

Muhlenbergia capillaris – Muhly grass, Hair

Planted in the northwest corner of the Arboretum, our plot of muhly grass is in its third year. When first planted they are pretty thin and unimpressive, but once mature these grasses really put on a show, especially if planted in large groups. Vibrant pink seed heads appear in late summer and persist in a thick cloud of color all through fall. Extremely drought tolerant, they hardly need watering once established. They require excellent drainage, best planted in gritty soils, or on a slope.

M. capillaris is native to the southeastern US. Map by USDA plants database.

Muhlenbergia reverchonii – Seep Muhly

Usually smaller in stature, this grass is notably less stiff. While M. capillaris grows straight up, the graceful blades of seep muhly are arching and curled. It isn’t as deep in color, but still has a nice pink hue that is slightly more airy and light. Better for folks who prefer more neutral tones. This species has much more movement in the wind, and is softer to the touch. Something to think about when installing grasses around play areas or walkways!

M. reverchonii has a more limited range, found in the central regions of Oklahoma and Texas.

Muhly Grass cultivars

‘White Cloud’ muhly grass, photo courtesy of Hoffman Nursery

There have been some great options on the market for Muhly grass cultivars in recent years, including a variety of M. capillaris called ‘White Cloud’. It has all the allure of those wispy seed heads but in an ethereal white, a perfect pop for darker backdrops like brick or evergreens. At 4 ft tall it grows a bit taller than the pink types and can be used as a fluffy, neutral tone backdrop in the garden. Muhlenbergia ‘Undaunted’ is a well-loved cultivar of M. reverchonii. It’s weeping seed heads and open habit make it a great specimen plant for the perennial border.

‘Undaunted’ is noted over the straight species for increased hardiness in norther zones and having a deeper panicle color at first flush. Photo courtesy Walter’s Gardens

No matter which Muhly grass you choose, as long as you plant in full sun and well draining soil, you will surely be thrilled with its light texture and season-long interest. It is a water-wise plant with no major pest problems, but it does have few flaws: collapses easily in heavy snow, not very hardy in northern zones, and doesn’t always establish well when planted in fall. Keep those things in mind when considering adding this grass to your landscape. Look out for the spring update of the Native Plant Guide on our FloraKansas page to find out what species we will have available at our spring sale.

Right Rudbeckia, Right Place

Posted on by Katie Schmidt

Rudbeckia is a very recognizable flower. Its bright yellow blooms appear when summer reaches its peak, and flowers steadily through the hottest part of the summer when we all need it most. Also known as black eyed Susan (named after a romantic poem!) or sometimes as yellow coneflower, Rudbeckia is a variable genus with many garden worthy species. But they each want a little bit different environment, so be sure to put them in the right place!

Rudbeckia maxima – Giant Coneflower

Photo by Eric Hunt, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons

R. maxima is a lesser known species native to the southern US, including Oklahoma and Texas. It averages about 6 feet tall in our area, but can be taller in moist, fertile soils. The flowers attract pollinators all through July, and through the winter a bevy of birds perch on the cones and eat the nutritious seeds. The foliage is striking: waxy and grey, resembling cabbage leaf. A wonderful vertical element to add to your landscape, with very sturdy stems and large blooms. It is a show piece in the garden! But it can easily be floppy if it gets too much shade or the soils are too rich. Situate it in strong sun and semi-dry soil, with dense grasses around it for support.

These R. maxima are thriving on the dry side of our drainage ditch near the greenhouse. The cones were huge this year!

Rudbeckia subtomentosa – Sweet Coneflower

Sweet coneflower is often found in moist sites, as seen here growing on the banks of the Arboretum pond. This plant can handle a bit of dry soil once established, but in general it likes moist sites. So try to plant it in a low spot or drainage area. The common name references the subtle sweet smell of the blooms. Less spready than other species of Rudbeckia, it pairs well in the garden with grasses like Panicum and other tall forbs like Eryngium yuccifolium. The petals can vary in length, and sometimes they are even rolled or ‘quilled’ as seen in the cultivar ‘Little Henry’.

Rudbeckia triloba – Brown Eyed Susan

Clouds of small yellow blooms on stiff, wiry stems appear in mid to late June on this easy to grow perennial. It readily self seeds, to the point of becoming an absolute menace in the garden! But if you have the space to let it run wild it is a pollinator-attracting powerhouse. It is best planted in an area that can be contained, either by mowing, burning or hemmed in by sidewalk/pavement. This species is native throughout most of the eastern half of the continental United States, and grows well in full to part sun and average to moist soil. The cultivated variety called ‘Prairie Glow’ flowers red with yellow tips. It is a seed strain from breeder David Cavagnaro introduced to the garden trade in 2003. Both the straight species and the cultivar are often available at FloraKansas.

Rudbeckia missouriensis blooming in the Gjerstad garden on the northwest side of the Arboretum.

And beyond these three, there are tons more to choose from! In a previous post, Scott talked a bit about R. missouriensis, R. hirta, R. lacinata, and R. fulgida, all great options for the habitat garden. All of these and more are usually available at our biannual FloraKansas event, so be sure to keep your eyes peeled for our updated plant list when it comes out.