Dr. David Graper is a professor of Horticulture at South Dakota State University. He’s selected some fall flowers that grow in the region like the asters below. See the link to his article:
http://igrow.org/gardens/gardening/fall-color-in-the-flower-garden/
Dr. Graper is also Coordinator of the South Dakota Master Gardeners. If you want find out more about the 2017 Master Gardener training, go to the same link above and find “Master Gardeners” on a drop down menu of the Igrow.org website.