Blue sedge. This low-growing, blue-green sedge is perhaps one the best spreading forms we grow, slowly spreading by rhizomes to form dense patches of finely textured groundcover. Native to Europe, blue sedge grows best in full sun with moderate water; it will tolerate a wide range of soils. Plants from seed are highly variable and can range in size from 6-24” tall, though withholding water will keep plants more compact. Hardy below 0F. Europe.