Sagina subulata
A low, cushion-forming perennial that creates a dense, moss-like carpet of fine emerald-green foliage just one to two inches tall, spreading slowly to about a foot. It favors full sun to partial shade with consistent moisture and well-drained soil, and does not tolerate prolonged drought or heavy foot traffic. Tiny white star-shaped flowers dot the surface in late spring and summer. Use it as a fine-textured filler between flagstones and pavers, as a small-scale lawn substitute in cooler microclimates, and to soften borders, rock gardens, and pathway edges.