Botanical Name: Pennisetum setaceum ‘Rubrum’ Common Name: Purple Fountain Grass Hardiness Zone: Perennial in USDA Zones 9–11; Grown as an Annual Elsewhere Size: 36–48" Tall × 24–36" Spread Growth Habit: Upright, Arching, Fountain-Like Habit Sunlight: Full Sun Soil: Well-Drained Soil; Tolerates Average to Poor Soils Water Needs: Low to Moderate; Drought Tolerant Once Established Bloom Season: Summer to Fall Fertilizer: Minimal; Avoid Excess Fertility Features: Deep Purple Foliage, Soft Bottlebrush Plumes, Heat Tolerant, Fast Growing Uses: Containers, Accent Plantings, Mixed Beds, Mass Plantings, Tropical & Modern Landscapes Patent: ❌ Not Patented Propagation: ✔ Propagation Permitted

More About Purple Fountain Grass

Purple Fountain Grass is prized for its rich color, graceful movement, and strong seasonal presence. Narrow, burgundy-purple blades arch outward to form a classic fountain shape, while soft, bottlebrush-style plumes rise above the foliage in mid to late summer. Together, the foliage and flowers create constant motion, adding energy and drama to the landscape.

This grass thrives in heat and full sun, where color is deepest and growth is most vigorous. Once established, it handles drought well and requires little maintenance beyond routine watering and seasonal cleanup. Its fast growth and bold habit make it ideal for containers, focal points, and large mixed plantings where instant impact is desired.

Why We Like It (Our Trials)

In our trials, Purple Fountain Grass consistently delivered strong color and uniform growth throughout the summer season. Plants filled in quickly, held their fountain-like form without flopping, and remained attractive through heat and dry conditions. The plumes added texture without becoming messy or overwhelming.

We especially like it for gardeners who want bold, tropical-style drama with very little effort. Purple Fountain Grass pairs beautifully with bright annuals, silver foliage, and modern designs, providing height, movement, and rich color from planting through frost.

Rubrum vs. Other Grasses

Pennisetum ‘Rubrum’ is a classic purple fountain grass, valued for its deep burgundy foliage and dramatic presence. Compared to Pennisetum ‘Fireworks’, Rubrum is more uniform and bold, lacking variegation but offering stronger color saturation. It contrasts with Pink Muhly Grass by providing season-long color instead of a brief bloom display. Against Juncus varieties, Rubrum feels looser and more expressive.

Rubrum also differs from Carex ‘Red Rooster’, offering height and plumes instead of compact foliage. Compared to Acorus ‘Ogon’’, Rubrum prefers dry, sunny conditions and bold visual roles. It pairs well with structured grasses like Blue Arrow to balance softness and form. Rubrum remains your best grass for rich color, drama, and bold contrast in warm-season displays.