This perennial is for night owl gardeners, as the bright yellow flowers open in the afternoon and stay open all night. Nicknamed Missouri Evening Primrose (aka Night Candles), this tough, drought-tolerant perennial grows low to the ground and can spread 15 to 18 inches wide, making it an ideal candidate for hillsides, rockeries, xeriscapes, and any other low-water areas. This specimen prefers full sun, well-draining soil, and doesn't like to be moved once established, as it sends out long deep roots.