Silkgrass (Pityopsis graminifolia) is a short-lived perennial that grows to approximately 2-3 ft. high and 1-5 ft. wide so it's best to plant this 2 feet apart. Yellow flowers and white fruit make this a showy groundcover or a great addition to a wildflower garden. It blooms late fall to early winter. Deadhead flowers to keep it looking neat. It requires full sun with well-drained soil.