Purple fountain grass is a decorative and dramatic ornamental plant. With its gently arching red leaves and colourful purple flowers, this perennial can be used anywhere you'd like to generate visual interest. Tropical in nature, purple fountain grass is drought-tolerant, heat-resistant and grows to 6 feet in height. An eye-catching addition to the lawn, it requires almost no care throughout the growing season. It is not a cold hardy plant, however, and even in the South, purple fountain grass requires extra attention to survive the winter weather.
Evaluate your climate. If you live in an area where the temperature regularly drops below -6.67 degrees Celsius, purple fountain grass will need to be dug up and brought inside for the duration of the winter. Dig around the base of the plant, removing as much of the root system as possible, then place the clump of grass into a large container filled with potting soil. Set the container in a sunny, warm location where the plant will be protected from wind and cold drafts. Water the plant once every two weeks throughout the winter. When all danger of frost has passed, the grass can safely be replanted in the yard.
Allow the clumps of purple fountain grass to wither and fade if you live in an area known for having mild winter weather. Once the foliage has shrivelled and turned brown, trim the plant, removing any dried-up, dead or diseased leaves with a pair of sharp pruning shears. Cut the plant down to the ground, if necessary.
Spread a 4-inch layer of mulch around the base of the newly trimmed plant. This will insulate the roots and help to protect them from exposure to cold weather.
Cover the remaining tufts of fountain grass each night with old blankets or burlap bags. This will help to protect the fragile plant tissues from the damaging effects of chilly weather. Remove the coverings in the daytime to allow the plant to receive sunlight and fresh air.
Water the plant once a week for 15 to 20 minutes for the duration of the winter. If the plant is exposed to rain or other natural sources of moisture, skip watering that week as too much moisture can lead to root rot.