Spiderworts (Tradescantia spp.) and Day-flowers (Commelina spp.) are the only members of the Commelinaceae, the Spiderwort family in the Indiana flora. They are all monocots, with parallel leaf veins and flowers made of three parts or multiples of three.
There are four species of Spiderwort in the state. The common name comes from the arrangement of the flowers on the ends of the inflorescences with bracts underneath that curve back like the legs of a spider. We have Glaucous spiderwort (Tradescantia ohioensis) in the Butler Prairie. Flowers are a brilliant florescent blue in early June, especially on cloudy days. I bought some at the INPAWS auction a few ago that reliably bloom in my sunny front garden.
Virginia spiderwort (T. virginiana) and Zigzag spiderwort (T. subaspera) are found in woods. Virginia spiderwort blooms in late spring; Zigzag a little later in the summer. The fourth species in Indiana is a non-native found in the north.
Day-flowers get their name because they only last one day, opening in the morning and fading by day’s end. Ours in Marion County are Common Day flowers (Commelina communis), non-native but not fiercely invasive. I see them along the edges of the Butler Woods. The photos are from the front steps of the International School. The flowers are beautiful and delicate, with two pale blue petals and one white petal.