D Published September 17, 2012 at 1024 × 576 in Introducing the Platte River Sandhill Prairie Showy evening primroses in the restored sandhill prairie. Showy evening primrose, aka 4-point evening primrose (Oenothera rhombipetala) in restored sand prairie at The Nature Conservancy’s Derr Tract. 2002 seeding. Central Platte River, Nebraska