Clump-forming grasses, deciduous or evergreen, wiry leaves and airy flower heads. Some sources indicate over 300 species, across the world, especially arid areas, thus suited to open sites in the dry garden, with well drained soils. Too much fertility, or watering, may encourage too much lax growth. They are generally cool-season plants, coming into growth in the autumn and flowering late spring into summer. However, flowers and foliage will hold themselves into autumn and winter. Once flower stems begin to look untidy, these can be cut out, along with dead foliage. Come late winter, early spring, all foliage can be cut down to low hummock, to show off the emerging new leaves.