Herniaria glabra
Green Carpet, or rupturewort, is a dense, low evergreen mat-forming perennial that spreads to roughly 12 to 18 inches wide and stays only an inch or two tall, hugging the ground tightly. It prefers full sun to light shade and tolerates moderate to low water in well-drained soils, taking moderate foot traffic well. The tiny bright green leaves turn bronze to reddish in cold weather, and the inconspicuous greenish summer flowers are insignificant. Use it as a lawn substitute, between stepping stones and pavers, or to soften the edges of paths and rock gardens.