Here are some other plants I saw at the Mt. Cuba Center
. They were in their Prairie Garden but more located along a path at the top and growing individually or in clumps for educational purposes.
Heliopsis helianthoides var. scabra 'Summer Nights' is the orange ringed form of Western Sunflower or Ox-Eye Sunflower. The true species lacks the orange color and is a more solid yellow. This was definitely an eye catcher, with it's dark foliage and bright flowers, which cover the plant. I read that this species can be aggressive spreading but it's unclear weather that's by rhizomes or by seed. It's pretty enough that I might be willing to find out.
Stokesia laevis, Stokes' Aster. I was growing this in my garden for a time but it died out on me. They benefit from acidic soil apparently. Personally I don't know why this isn't planted instead of Bachelor Buttons. The flowers look similar enough in both shape and color. At least here you have a much bigger flower.
Stokes' Aster 'Peachie's Pick' is a purple flowering cultivar. I think they also come in white as well.
Allium cernuum, Nodding Onion. This wild onion is said to have an overpowering smell and taste, and thus it's culinary potential has been overlooked in favor of the varieties we use today. The wild onion still grows in the wild but can make a nice addition to the garden too. Personally I'm not a fan of this plant but I may one day get around to getting some. It's just not on the top of my list.
They had a lot more stuff flowering there but I don't always take good photos. Their forest was absolutely blooming with Black Cohosh or Bug Bane, I forget which flowers sooner. I have Bug Bane but it rarely does well in my garden.