Perennial grasses, once set, will flourish year after year. Annual grasses, on the other hand, complete their life cycle within a year and must be reseeded annually. Low-maintenance grasses like annual rye, cereal rye and annual bromegrass are suited for rocky soils and other hard-to-grow areas. Annual grasses grow quickly from seed and provide a temporary ground cover. This makes them a good alternative until perennial grasses are established. Perennial grasses like wheatgrass and hairgrass are suited for rocky terrain and require only one seeding.
Thick, long, rough pasture grasses are low-maintenance and suited for rocky conditions but are not always a good match for a residential lawn. Low-maintenance turf grasses for rocky areas include: hard fescue, big bluegrass and squirreltail grass. Hard fescue is slow to establish so it should be sown with a fast-growing grass, like wheatgrass.
Ornamental grasses are a solution to problem lawns or rocky regions within an otherwise smooth lawn. These grasses are planted in stands or clumps and provide a break in a garden or landscape's monotony. They are usually tall, prairie grasses that have adapted to poor soils and drought conditions. Some are lower ground covers but all are relatively low-maintenance. Ornamental grasses are also suited for slopes, ditches or other uneven surfaces that require ground cover. Some choices for rocky soils include June grass and silky threadgrass.
Healthy grass is the best way to prevent moss growth, a frequent problem in rocky, wet environments. Keep your grass healthy by aerating it as needed and by fertilizing it. Even low-maintenance grasses require some assistance in difficult environments. Choose grasses that are native to your area as they will require less work. Learn about the grasses that are invasive in your area. Bromegrass, for instance is invasive in areas throughout the midwestern United States. Consult with your local master gardener to learn about the grasses that are invasive in your geographic region. Planting invasive grasses puts native plants at risk.