Flowering now at JLBG is one of our cute Southeastern natives known as Bog Buttons (Lachnocaulon anceps). The entire family, Eriocaulaceae, has a similar stature with small grass-like foliage, topped by these long antennae-looking structures. In the wild, these can be found in low, often flooded ditches, but they are easily grown in constructed bog gardens. I expect if these were from a more exotic location, more people would grow them. We think they are pretty darn cute.
Would love to buy this for a wet container garden.