Why Plant Taller Ornamental Grasses?
Ornamental grasses are valued for seed heads, seasonal color, graceful movement, and wildlife benefits. Sizes range from 6 inches to 8–10 feet. Blade color spans striped, blue, bright or dark green, maroon, yellow, tan, and variegated. These grasses perform in mixed gardens, as erosion barriers, in containers, as specimens, and in meadows. The following sections focus on larger, sun-loving varieties.
Panicum (Switchgrass)
Overview.
Switchgrass (Panicum virgatum) is native across North American savannas, swamps, forests, and roadsides. Of more than 450 species, roughly 75 cultivars are commonly available. Historically dominant in tall-grass prairie, switchgrass provides critical winter cover for birds. It prefers full sun and tolerates a wide range of soils. Prune to 8–10 inches in early spring; fall cutbacks combined with wet winters can lead to crown rot. Deep, fibrous roots (5–6 feet) make it excellent for erosion control. Seeds were historically ground for flour by Indigenous peoples. It performs well even under Juglans nigra (black walnut).
Cultivars.
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‘Shenandoah’ — Upright; emerges green in late spring, turning reddish-maroon by summer. Airy seed panicles held above the foliage feed songbirds. ~4' tall × 3' wide.
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‘Heavy Metal’ — Strongly upright metallic-blue blades; ~5' × 3'. Light seed panicles in mid-summer contrast beautifully with foliage.
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‘Northwind’ — Very vertical with upright blades; ~5–6' × 3'. Blue-green foliage with tan seed heads; stands up to wind and snow.
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‘Dallas Blue’ — Upright to vase-shaped clumper; blue-green foliage; ~6' tall. Mid-summer light-brown seed panicles; wind- and rain-resistant, maintains form.
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‘Purple Tears’ — ~4' tall; green blades; seed panicles emerge soft gray, opening to purple-hued heads. Mass plantings create a “smoky” effect when in bloom.
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‘Cloud Nine’ — Tall and airy to ~8'; bluish-gray blades, light-tan panicles, golden fall color; excellent as a backdrop with notable movement.
Miscanthus (Maiden Grass, Chinese/Japanese Silver Grass)
Overview.
Miscanthus is native to Asia; some types can reseed readily and are listed as invasive in certain states. Breeders are developing sterile/infertile cultivars; gardeners seeking to avoid reseeding should choose late-blooming or infertile selections. Grow in full sun with moist, well-drained soil. Do not prune until early spring—wet winters can rot the crown if cut back in fall.
Cultivars.
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‘Bandwidth’ — Infertile, gold banding on blades, late-summer bloom; upright ~3'. Great late-season color; prefers sun and moist, well-drained soil.
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‘Purpurascens’ — Upright to ~5'; late summer to early fall bloom; exceptional red fall color lasting 8–10 weeks; hardy to Zone 4; not drought tolerant.
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‘Adagio’ — Smaller, with narrow green blades; tan-beige inflorescences in summer; ~4' tall; refined texture for formal settings.
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‘Gracillimus’ — Rounded form, fine green blades; late bloomer (often mid-September); ~6' tall; reddish seed heads; full sun, moist, well-drained soils.
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‘Little Kitten’ — Fine green blades, ~2–3' tall; sparse to no flowers; reliable as a border.
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‘Morning Light’ — White-variegated fine blades; resists flopping; excellent in large containers; reddish flowers from late summer; ~6' including bloom; tolerates light shade.
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‘Zebrinus’ — Yellow horizontal bands; reddish-brown flowers in September; can fold in wind; ~8' including bloom; full sun for best color.
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‘Cabaret’ — Wide leaves, green margins with bold white bands; requires long, warm season to flower; spectacular variegation; blooms late September; ~9'; hardy to Zone 6.
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‘Strictus’ (Porcupine Grass) — Variegated blades projecting outward; upright; ~9'; hardy to Zone 5; September bloom, distinctive “quill” look.
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‘Morning Light’ (noted again as a best-known selection) — Narrow foliage with white margins; reddish flowers in September; tolerates light shade; ~6'.
Pennisetum (Fountain Grass)
Overview.
Fountain grasses feature bottlebrush plumes in tan, pink, black, or white. Plants mound, with arching blades and plumes above. They grow in full sun to part shade; some are perennial in the Mid-Atlantic, others annual—verify hardiness at purchase. Leave foliage standing through winter; prune to ~6" in early spring. Originating in Eastern Asia, some species are invasive in western states. Tolerant of wet soils, drought, black walnut, and air pollution; helpful for erosion control.
Selections.
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P. alopecuroides ‘Little Bunny’ — True dwarf to ~1'; light-tan, ~1" bottlebrush plumes; bright-green blades turn tan in fall; seeds eaten by birds; Zones 6–9.
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‘Burgundy Bunny’ — ~1.5' tall × 2.5' wide; green blades with burgundy highlights turning fully burgundy in fall; small white plumes; sun/part shade; Zones 6–10.
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‘Hameln’ — ~2.5' × 2.5'; green blades with tan plumes in late summer; yellow-to-brown fall color; stands through snow for winter interest; Zones 5–9.
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P. orientale ‘Karley Rose’ — Medium green blades, pink plumes summer to fall; arches to ~3' wide; plumes to ~3' tall; Zones 6–8.
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P. alopecuroides ‘Red Head’ — Larger selection; red-tinged plumes held above a ~4' × 4' clump; great dried or fresh; full sun, moist soil.
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P. setaceum ‘Rubrum’ — Annual in Zones 9–10; striking red-burgundy foliage; ~3–4' tall and wide; best in pots; full sun.
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P. setaceum ‘Fireworks’ — Annual (Zones 9–10); ~3' tall; arching blades in green, burgundy, pink, and white; excellent for containers; full sun, moist soil.
Fescue (Festuca)
Overview.
Cool-season, vibrant blue selections that dislike overwatering and hot, humid conditions. Best in full sun, airy exposures with afternoon shade. Evergreen with narrow blue-gray blades.
Varieties.
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‘Elijah Blue’ — Tight mound to ~12"; blue seed heads in early summer; needs well-drained soil or containers.
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‘Cool As Ice’ — Mounds to ~10"; similar color with better humidity tolerance; blue seed heads in early summer; great in pots.
Andropogon gerardii (Big Bluestem, Turkey Foot)
Native warm-season clumper for moist or dry soils; ~5–8' tall with blue-green blades. Fall brings burgundy tints and a three-parted seed head resembling an upside-down turkey foot. Fall/winter color ranges from yellow to copper; remains upright in snow. Excellent wildlife cover and food.
Arundo donax (Giant Reed Grass)
Historic source of reeds for wind instruments. Rapidly forms a screen/border to ~12–14' tall and wide within three seasons. Seeds develop only in warmer climates. ‘Variegata’ offers cream-striped blades and is hardy to Zone 6. Full sun to very light shade; tolerates wet and dry soils.
Chasmanthium latifolium (Indian Wood Oats, River Oats)
Native to river bottoms/moist thickets; also grows in dry shade and under black walnut. Mid-summer oat-like inflorescences nod over blue-green blades, turning copper-brown in winter and attractive in snow. Valuable wildlife food. Reseeds aggressively—cut seed heads before maturity to control spread. Prune in spring before new growth. ~2–3' tall; clump-forming; excellent for erosion near water.
Cortaderia selloana (Pampas Grass)
South American native; hardy roughly to Zone 8. Reaches ~10' tall; valued for fresh and dried arrangements. Prefers moist summers, full sun, and well-drained soil; drought tolerant once established. Not reliably perennial in the Mid-Atlantic.
Deschampsia (Tufted Hair Grass, Tussock Grass)
Clump-forming with dark-green basal blades. Panicles begin green in June and turn gold. To ~4' including bloom. Long-lived, adaptable to many soils; prefers full to part sun; hardy to Zone 4.
Eragrostis spectabilis (Purple Love Grass)
Native to sandy soils; blue-gray blades form billowing mounds topped with arching purplish-pink flower clusters beginning late August. Requires sharp winter drainage; useful for stabilization. ~2' overall; hardy to Zone 5.
Helictotrichon sempervirens (Blue Oat Grass)
Larger, thicker blue blades; cool-season; hardy Zones 4–8.
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‘Sapphire’ — ~2–3' tall and wide; tan seed heads in early summer; needs well-drained soils and full sun; provide afternoon shade where humid.
Muhlenbergia capillaris (Pink Muhly Grass)
Native to sandy/rocky soils and open woodlands. Dark-green glossy blades topped by clouds of pink to pink-red panicles from September through November. ~3' overall; clump-forming; best in full to part sun; hardy to Zone 6. Will not tolerate wet winters.
Nassella tenuissima (Mexican Feather Grass)
Native to dry open ground and rocky slopes; extremely fine, hair-like blades with feathery tan inflorescences that move elegantly in breeze. Full sun to light shade; hardy to Zone 6. Avoid clay, wet winters, or water on the crown.
Schizachyrium scoparium (‘Little Bluestem’)
Native to tall-grass prairies/open woods; clump-forming, drought-tolerant; ~2–4' tall. Fine-textured blades shift from green/blue-green to magenta and copper in fall. Excellent food source for songbirds. Requires full sun and well-drained soil.
Sorghastrum nutans (Indian Grass)
Warm-season native; second most prevalent in tall prairies. Upright to ~5', to ~7' in flower. Thin green blades turn golden-orange in fall. Showy plumes with yellow anthers in August; good dried. Full sun; handles varied soils including clay. Valuable to wildlife and native songbirds. Prune to 6–8" in early spring.
Sporobolus heterolepis (Prairie Dropseed)
Threadlike blades form fine-textured mounds. Glossy-green summer color turns deep copper-orange from late September through winter. Seed heads rise above clumps from late August into September and are loved by migrating birds. Excellent for erosion control and drought tolerance once established. Slow to size up but long-lived.
