Purple Fountain Grass
Cenchrus setaceus 'Rubrum' (formerly Pennisetum setaceum 'Rubrum') · Warm-season, Perennial (Tender), C4 Carbon Fixation
Grass Family
Poaceae, Subfamily Panicoideae, Tribe Paniceae
Grass Category
Ornamental Grass
Variety / Cultivar
'Rubrum'
Hardiness Zones
USDA Zones 9-11; not frost-tolerant (treated as an annual in zones 1-8); goes dormant or dies when temperatures drop below 32°F.
About This Grass
An upright, arching, mounded ornamental grass known for its burgundy-purple foliage and showy, feathery, pinkish-purple flower spikes (panicles). Growth is dense and clumping, reaching 3-5 feet in height when unmowed.
Blade Characteristics
Narrow, arching blades (medium width 3-6mm); burgundy, reddish-purple to deep bronze in color; flat to slightly channeled; pointed tips. Vernation is rolled; ligule is a ring of short hairs; auricles are absent.
Root System
Fibrous and dense; moderate depth; slow to establish in cold soils but rapid in heat; does not form thatch or sod like lawn grasses; low wear recovery.
Growing Information
Origin Region
Native to Africa, Southeast Asia, and the Middle East; commonly cultivated in USDA zones 9-11 and used as an annual in cooler climates.
Growth Habit
Bunch-type (clumping), rapid upright growth, does not spread by rhizomes or stolons.
Sunlight & Water Needs
Full Sun (6+ hours); moderate water needs during establishment but highly drought-tolerant once mature; prefers well-drained loamy or sandy soils with neutral pH.
Mowing & Maintenance
Low maintenance. Not used as a turf grass; should not be mowed like a lawn. Instead, it is cut back to 3-5 inches above the ground in late winter/early spring to encourage new growth.
Special Characteristics
Superior deer resistance; high drought tolerance; salt tolerant; unique maroon color provides landscape contrast; feathery seed heads are popular for cut floral arrangements.
Ecological Information
The 'Rubrum' cultivar is generally sterile (non-invasive), unlike the green parent species which is invasive in Hawaii and the Southwest US. Provides cover for small birds and insects.