Culture
Warm season tender perennial grass that is winter hardy to USDA Zones 8-10. It is grown as an annual north of USDA Zone 8. This grass performs best in medium moisture, well-drained soils in full sun. It appreciates consistent water throughout the growing season. It can be dug in fall, trimmed, and overwintered in greenhouses or indoors in sunny cool areas in cold winter climates, but many gardeners simply prefer to purchase new plants each spring. Tall plants may need some staking or other support and should be sited in areas protected from strong winds. When grown as a perennial, species plants can become invasive self-seeders. Species plants are not currently recommended for landscape use in warm winter areas where freezing temperatures typically do not occur prior to December 1 (USDA Zones 9-10) in large part because plants will flower, seed and self-seed invasively in such conditions.
Noteworthy Characteristics
Pennisetum purpureum, often commonly called napier grass, cane grass or elephant grass, is a large, tender perennial grass native to tropical and sub-Saharan Africa but has been widely introduced to tropical and subtropical regions around world as a forage crop and ornamental grass. It is a rapid-growing, clump or colony-forming grass that produces upright arching, narrow, linear, green leaves in dense clumps growing to 15' tall. Plants spread by seeds or underground rhizomes, forming dense stands. This plant has escaped cultivation and is considered invasive in warm, frost-free regions of Asia, Europe, North and South America, and Oceania. Check local laws or invasive plant lists before adding this plant to your landscape.
Genus name comes from the Latin penna meaning "feather" and seta meaning "bristle" in reference to the flowers having long, feathery bristles.
Specific epithet means purple.
Problems
No serious insect or disease problems.
Uses
Provides excellent texture, color and contrast to borders, foundations and open areas. As an annual, it may be grown as a specimen, in groups or massed. It may spread invasively in warm winter areas where plants will flower and set seed. Containers.