Fountain grass (Pennisetum alopecuroides)
Pennisetum alopecuroides, or Fountain grass, offers showy plumes, low maintenance, and drought tolerance for US Zones 6-9.
Complete Plant Information
Overview
Pennisetum alopecuroides, commonly known as Fountain grass, is a highly valued warm-season ornamental grass prized for its arching habit and spectacular late-season plumes. These flowering spikes emerge in late summer, arching outward like water spraying from a fountain, giving the plant its distinctive common name. The fine texture of its foliage provides excellent contrast against broad-leafed perennials in the landscape.
This clump-forming grass is robust, offering aesthetic appeal from summer through winter, with leaves turning golden yellow in the fall before fading to beige. Pennisetum alopecuroides is relatively adaptable, thriving in average soils as long as it receives adequate sunlight, although excessive shade can diminish its flowering performance. It presents a low-maintenance solution for adding movement and vertical interest to borders and naturalized areas.
Cultivars of Fountain grass are widely available, introducing variations in size and flower color, but it is important to remember that plants grown from seed may not breed true to type. Experienced gardeners appreciate the reliability of Pennisetum alopecuroides for its texture, structure, and relatively few pest or disease issues.
Fast Facts
- Plant Family: Poaceae
- Plant Type: Ornamental grass
- Native Range: Eastern Asia to western Australia
- Hardiness Zones: USDA Zones 6-9
- Size at Maturity:
- Height: 2.5-5 ft
- Spread: 2.5-5 ft
- Bloom Time: July to February
- Bloom Description: Silvery to pinkish-white
- Sun Exposure: Full sun to part shade
- Water Needs: Medium to wet
- Maintenance Level: Low
How to Grow
The ideal time to establish Pennisetum alopecuroides is in spring after the danger of frost has passed, or once soil temperatures have warmed sufficiently for this summer-growing grass. Location selection is key; while Fountain grass tolerates part shade, ensure it receives full sun for the best flowering display. It easily grows in average soils but specifically enjoys medium to wet conditions, making it suitable for less-than-perfect drainage areas near the periphery of ponds or swales.
Water needs are medium to wet, though established clumps show good tolerance to drought conditions. Avoid constant saturation if possible, except when intentionally planting in rain gardens or wet areas where it excels. Fertilization is rarely required; overly rich soil can lead to floppy growth, diminishing the elegant fountain shape.
Pruning is a major component of low-maintenance care for this ornamental grass. Cut all foliage back to the ground in late winter or very early spring before new shoots begin to emerge. This practice keeps the plant tidy and encourages vigorous new growth throughout the season. Be aware that while it can self-seed, cultivars may not remain true to type, requiring vigilance if aggressive reseeding becomes problematic, especially outside of Zone 6 in colder regions.
Landscape Uses
The unique texture and structure of Fountain grass make it an outstanding architectural element in garden design. Use it as a specimen plant where its arching plumes can be fully appreciated, or plant in groups or masses to create sweeping swaths of movement. Its suitability for use as ground cover or in rain gardens highlights its adaptability to different moisture levels.
Pennisetum alopecuroides provides crucial contrast against broad-leaved shrubs and perennials, softening hard lines found in foundation plantings or borders. Its tolerance for wet soil also positions it perfectly at the edge of water features, such as ponds or streams, integrating it into aquatic or bog-like plantings. For erosion control on slopes, its dense clumping habit establishes an effective stabilizing root system.
Consider pairing this grass with plants requiring similar sun exposures but offering contrasting colors or textures, such as coneflowers or salvias, to maximize visual impact throughout the bloom season extending into late fall and early winter.
Standout Features
Flower Qualities
- Showy
- Good Cut
- Good Dried
Noteworthy Characteristics
Pennisetum alopecuroides, commonly called fountain grass, is a warm season, clump-forming grass native to grassy hillsides, roadsides, and meadows in East Asia. Mature clumps will reach 2.5-5’ tall with an equal spread, featuring narrow, medium to deep green leaves that turn golden yellow in the fall. Showy, silvery to pinkish-white, bristly, bottle brush-like flower spikes arch outward from the clump in late summer, persisting until late fall or early winter before shattering. The genus name references the feathery bristles on the flowers, adding to this grass’s elegant presentation.
Tolerances
- Drought
- Erosion
- Wet Soil
- Black Walnut
- Air Pollution
Potential Problems
Fountain grass generally exhibits no serious insect or disease problems, which contributes significantly to its low maintenance rating. The primary concern for gardeners planting Pennisetum alopecuroides is its potential to self-seed aggressively in ideal conditions. If you wish to strictly control its spread, select named cultivars over seed-grown varieties or deadhead the flower spikes before the seeds fully shatter. In colder zones near the edge of its hardiness range (like Zone 5), winter kill can be an issue; ensure it is situated in a protected microclimate for the best chance of overwintering.
Frequently Asked Questions
What hardiness zones is Fountain grass suitable for?
Pennisetum alopecuroides is reliably hardy in USDA Zones 6 through 9.
How large does Pennisetum alopecuroides grow?
Mature clumps typically range from 2.5 to 5 feet in height with a corresponding spread of 2.5 to 5 feet.
What sun exposure does Fountain grass need?
This ornamental grass thrives in full sun but can tolerate partial shade, though flowering may be reduced significantly in shadier spots.
When does Pennisetum alopecuroides bloom?
Fountain grass produces its characteristic silvery to pinkish-white plumes from July and often continues blooming well into February.
Conclusion
The inherent beauty and resilience of Pennisetum alopecuroides ensure its status as a landscape favorite, offering exceptional texture and movement with minimal effort. Its ability to handle moist soils while also tolerating drought makes this Fountain grass highly versatile across various garden settings. Before planting, confirm that your site falls within USDA Zones 6-9 and plan for a late winter cleanup to welcome its return next season.
Companion Planting
Because Pennisetum alopecuroides prefers medium to wet soils and full sun, companion plants should share these requirements to ensure overall garden health. Excellent partners include flowering perennials that offer strong structure, such as Rudbeckia (Black-Eyed Susan) or ornamental salvias, whose upright habits contrast nicely with the weeping form of the grass. For areas near water features where it thrives in wetter soil, consider marsh marigold or Iris sibirica, provided they also tolerate the intense summer sun required for peak fountain grass performance.
Propagation Tips
While many gardeners purchase named cultivars of Fountain grass for guaranteed traits, Pennisetum alopecuroides can also be increased via seed or division. If grown from seed, be aware that self-seeding can sometimes be aggressive, leading to unexpected offspring that may not match the parent plant’s characteristics. The most reliable method for multiplying established clumps of specific cultivars is division. Perform this task in late winter or early spring just before new growth initiates, digging up the clump, dividing it into manageable sections using a sharp spade, and replanting immediately.
