A prairie plant equally at home in yards and public parks
Tradescantia sp. (spiderwort)
There are three species of native spiderwort commonly found in Nebraska (Tradescantia bracteata, Tradescantia occidentalis, and Tradescantia ohiensis) and another that is listed as rare (Tradescantia hirsutiflora) based on BONAP. T. ohiensis is easily the most commonly planted urban communities, but T. bracteata is available from plenty of nurseries as well.
Both T. ohiensis and T. bracteata thrive in hot, dry locations typical for Nebraska urban prairies. They can both be aggressive seeders, but I have not found them to choke out many long-lived native plants (especially those that are taller). Both are fairly short (with T. bractea shorter, usually less than 2' tall), and they rarely flop over. These characteristics make them ideal for public spaces lining concrete paths where the local conditions can be especially hot and dry.
At our home, both T. ohiensis and T. bracteata line our brick path through the garden area. They poke out between shorter sedges and bunch grasses that collectively work to suppress weeds. Both species bloom in May in our yard, giving a much needed early boost in insect activity after a long summer.
Spiderworts are interesting in that they make a new flower each morning that wilts away in the mid-day heat. If you want to see the pollinator activity on these plants, you'll want to get out before noon.
Prior to blooming, the buds of Tradescantia have their own interesting form. They hang like a cluster of grapes, each patiently waiting to try their luck at pollinator attraction. As a prolific seeder, they must have some success.
As an early-season bloomer, Tradescantia supports some of the earliest active insects. I find flies, such as flower flies in the family Syrphidae, are some of the first species to visit flowers.
When few other species of bee are flying about, Lasioglossum sp. are a reliable visitor to watch. They are small and not ornately colored, but their acrobatics are entertaining enough. Through a macro lens or a magnifying glass, these bees' antics can entertain an observer for hours.