Purple fountain grass is a hardy ornamental grass that grows naturally in several warm-climate areas, especially in U.S. Department of Agriculture plant hardiness zones 8 through 11. Be careful in your choice of this ornamental grass as both the state of California and the state of Florida have classified fountain grass as an invasive weed, although the purple variety does not produce seeds and is less invasive than other varieties. Once established it is extremely drought resistant and pest free. Prune your purple fountain grass in late autumn, just before the first frost.
Wipe down your shears and your trowel with a cloth saturated with rubbing alcohol in order to prevent the spread of any diseases while trimming your fountain grass.
Tie a string around the fountain of grass that you are about to cut in order to make your job a bit easier. Use your shears to cut the fountain grass horizontally approximately 2 to 4 inches above the soil line, as if you have given your clump of grass a flattop haircut.
Use your fingers, shears and your trowel to dig and pull out any dead grass within the clump.