Purple fountain grass (Pennisetum setaceum 'Rubrum') is an ornamental grass used in the landscape or in containers. It may be either an annual or a perennial depending on your gardening zone.
Zones 1 through 8
Purple fountain grass is an annual in U.S. Department of Agriculture plant hardiness zones 1 through 8, meaning that it will not survive the winter. Purple fountain grass is hardy down to temperatures of 20 degrees F. Since winter temperatures reach 20 degrees F or lower in zones 1 through 8, purple fountain grass will grow as an annual in these areas.
Zones 9 and 10
Purple fountain grass can be grown as a perennial in zones 9 and 10. Because winter temperatures in these zones do not reach lower than 20 degrees F, purple fountain grass will survive the winter and will grow as a perennial.
Regardless of your gardening zone, you can grow purple fountain grass in containers or in your landscape. It grows 30 to 36 inches tall, and needs to be located where it receives partial to full sunlight.