• Large-plumed pampas grass grows in clumps.Jupiterimages/Photos.com/Getty Images
  
  Ornamental grasses are indigenous to North American prairies, South American pampas and throughout similar environments in Asia and Central Europe. Ornamental grasses are adaptable and well-suited for home gardens, xeriscape landscape, parking lot boundaries and commercial areas. Perennial grasses provide texture to winter landscapes and color in the fall. Some ornamental grasses have spreading root systems, while others grow in clumps, but all are architectural plants, providing dramatic backdrops or a border frame. Annuals, as well as perennials, display large plumes in spring and summer and can complement other plantings as the seasons progress.
  
  

Rhizomatous

• Rhizomatous plants propagate through their root system as well as through seed. The seeds tend not to be viable, but the root systems spread underground and send shoots to the surface. Also known as "running" grasses, these plants are seldom planted as borders or within beds. Their rapid growth will out-compete flowers and other garden plants. Cordgrass, ribbongrass, lymegrass and some bamboos regenerate in this manner. Grasses with this propagation style are considered invasive, and controlling their spread can be difficult.
  
  

Clumping

• Clumping grasses are seen more frequently in landscapes than rhizomatous grasses. Fescue, miscanthus, switchgrass, fountain grass and some bamboos are clumping, meaning that they grow in small, localized groups. Grasses with this growth pattern have adapted to conserve water and protect themselves from low temperatures and extreme sun. They are easier to control in a garden than running grasses. Some varieties do well in dry soils, while others prefer moderately moist conditions, making them highly adaptable for a number of landscapes. When sited correctly, grass plants can thrive for up to four years. Since many grasses are native to North America, those living in the United States can consult with their local university extension master gardeners to determine the hardiest, low-maintenance grasses for their location.
  
  

Propagation And Control

• Rhizomatous grasses can be invasive and aren't suited for low-maintenance gardens, but gardeners willing to take the time to control and maintain running bamboos and ribbongrass can dig up the plants and propagate them by division, or discard. Clumping grasses propagate via seed. In certain areas, clumping grasses are invasive. Some gardeners cut back the heads of ornamental grass before seeds become viable.