Wine Cup is native to TX, OK and KS but grows in many other states surrounding us.
The photo on the right is one we took this summer at Missouri Wildflower Nursery. I wrote an article about the nursery and bought a pack of seeds to plant in our gardens. I've had mixed success but do not have a dedicated bed for them like they do.
Winecup is a low growing, sprawling, groundcover that has gorgeous flowers that close each evening.
They flower generously in the late spring and then disappear during the heat of the summer months.
Most advice says they prefer full sun but you can see from their planting, part shade can also work.
They like soil that drains well and can even enjoy sandy or gravelly soil for that reason. Try in rock gardens, at the edge borders, as the spiller in wooden barrels, hanging baskets, and for meadow plantings.
Pruning the trailers when summer hits will help encourage fall flowering.
Fine Gardening adds that they are cold hardy in zones 4,5,6.
The flowers provide nectar for beneficial insects and butterflies. One butterfly, the Gray Hairstreak, raises its caterpillars on the leaves of Wine Cup.
Check out Missouri Botanical Garden article about butterfly gardening here. That photo is Wine Cups blooming at the same time as tropical milkweed. Unlikely timing but maybe they made it happen!