A row of tall grass makes a fast, soft screen that softens a fence line or blocks a view all summer and fall. Tall ornamental grasses for privacy include miscanthus (Miscanthus sinensis), big switchgrass cultivars (Panicum virgatum ‘Cloud Nine’ and ‘Dallas Blues’), and ravenna grass (Saccharum ravennae), which can reach six to eight feet in a single season. They green up in late spring, reach full height by midsummer, and hold their dried form well into winter. I plant them in a staggered row spaced a few feet apart so the clumps merge into a wall of movement. The trade-off with tall ornamental grasses for privacy is the seasonal gap: after I cut them in late winter, the screen is gone until the new growth catches up in early summer. They also need full sun to stand upright, since a shaded tall grass flops and opens up. Choose non-seeding cultivars to avoid spread.
What makes a tall grass work as a screen
A privacy screen needs four things: height, density, speed of fill-in, and year-round presence. Tall ornamental grasses can deliver three of the four, with year-round presence as the weak spot.
Height is easy. Miscanthus, big switchgrass, and ravenna grass all reach 6 to 10 feet (1.8-3 m) in good soil. The tallest ornamental grass I have grown is ravenna grass at 11 feet (3.4 m) in my zone 5b trial bed. Giant miscanthus can push 12 feet (3.7 m) in zone 6 with a long growing season.
Density is the second requirement, and the warm-season tall grasses deliver it. A mature miscanthus clump is 4 to 6 feet (120-180 cm) wide, with hundreds of stiff blades that block sight lines from any angle. The leaves are broad enough to fill the gaps between stems, creating a visual wall.
Speed of fill-in is the third requirement. A potted 1-gallon miscanthus planted in spring reaches 5 to 6 feet (150-180 cm) by August of its first year. By year three it has hit its mature height and width. That is faster than almost any privacy shrub, which typically takes three to five years to fill a similar space.
Year-round presence is where grasses fall short. After the late-winter cut, the screen is gone until new growth fills in by mid to late June. The window is roughly 8 to 10 weeks of bare ground in spring, which may be acceptable for many gardeners and not for others. The trade-off is that grasses deliver summer and fall density that no deciduous shrub can match.
The best tall grasses for a privacy screen
A short list covers most screening situations. Each grass has a different height, width, and look, but all reach the 6-foot (1.8 m) minimum needed for a useful screen.
Miscanthus is my go-to pick for show. Miscanthus sinensis cultivars reach 5 to 8 feet (1.5-2.4 m), with broad fountain-shaped clumps and showy plumes from August into October. ‘Morning Light’ has thin green-and-white striped leaves and reaches 4 to 6 feet (120-180 cm). ‘Gracillimus’ has narrow green leaves and reaches 5 to 7 feet (150-210 cm). ‘Adagio’ is the compact option at 3 to 4 feet (90-120 cm), useful at the front of a screen.
Giant miscanthus (Miscanthus x giganteus) is the tallest option, reaching 10 to 12 feet (3-3.7 m) in zone 6 with a long growing season. It is a sterile hybrid that does not self-seed, which makes it a responsible choice where fertile miscanthus would spread. Hardy in zones 5 to 9, it is reliable in zone 5b and warmer.
Big switchgrass is the native pick. Panicum virgatum ‘Cloud Nine’ reaches 7 to 8 feet (2.1-2.4 m) with a 3 to 4 foot (90-120 cm) spread and blue-gray foliage. ‘Dallas Blues’ reaches 6 to 8 feet (1.8-2.4 m) with wider, blue-purple foliage and purple seed heads. Both are hardy in zones 3 to 9 and tolerate heavy clay better than miscanthus.
Ravenna grass (Saccharum ravennae, also sold as Erianthus ravennae) is the tallest pick. It reaches 8 to 12 feet (2.4-3.7 m) in good soil with a 4 to 6 foot (1.2-1.8 m) spread. Hardy in zones 5 to 9, it produces silvery plumes in late summer that mature to tan. It is the closest a cold-climate gardener gets to pampas grass, though it is less showy than true pampas.
Big bluestem is the tall native pick. Andropogon gerardii reaches 4 to 8 feet (120-240 cm) with distinctive turkey-foot seed heads. It is hardy in zones 3 to 9 and supports native insects and birds that miscanthus cannot. The trade-off is that big bluestem has a wilder, less manicured look than the showy non-natives.
| Miscanthus 'Gracillimus' | 5-7 ft (150-210 cm) | 3-5 ft (90-150 cm) | 5-9 | Dense | Good from July through February |
| Miscanthus 'Morning Light' | 4-6 ft (120-180 cm) | 3-5 ft (90-150 cm) | 5-9 | Dense | Good from July through February |
| Giant miscanthus (M. x giganteus) | 10-12 ft (3-3.7 m) | 3-4 ft (90-120 cm) | 5-9 | Dense | Good from July through February |
| Switchgrass 'Cloud Nine' | 7-8 ft (2.1-2.4 m) | 3-4 ft (90-120 cm) | 3-9 | Dense | Good from July through February |
| Switchgrass 'Dallas Blues' | 6-8 ft (1.8-2.4 m) | 3-4 ft (90-120 cm) | 3-9 | Dense | Good from July through February |
| Ravenna grass (Saccharum ravennae) | 8-12 ft (2.4-3.7 m) | 4-6 ft (1.2-1.8 m) | 5-9 | Dense | Good from July through March |
| Big bluestem (Andropogon gerardii) | 4-8 ft (120-240 cm) | 2-3 ft (60-90 cm) | 3-9 | Medium | Good from July through February |
Planting a screen
The planting pattern matters as much as the cultivar choice. I plant privacy screens in a staggered double row, with the clumps offset by half the spacing distance. A double row fills in within one season rather than two, and the offset pattern prevents the gaps that a single row can leave when the clumps lean.
For a 30-foot (9 m) long screen, I plant 12 to 15 clumps in a staggered double row. The first row goes 3 to 4 feet (90-120 cm) in from the property line, and the second row goes 3 to 4 feet (90-120 cm) behind the first, with each clump offset so it sits between two clumps in the front row. The mature screen is a continuous wall of grass 6 to 8 feet (1.8-2.4 m) deep.
Spacing depends on the grass. Miscanthus at 3 to 4 feet (90-120 cm) apart fills in within one season. Switchgrass at 3 to 4 feet apart fills in within two seasons. Ravenna grass at 4 to 6 feet (120-180 cm) apart fills in within two seasons. The wider spacing is cheaper but slower.
I plant in spring, after the last frost. The screen fills in by August of the first year, though it does not reach full height until year two or three. By year three, the screen is mature and the only maintenance is the late-winter cut.
The seasonal gap
The biggest weakness of a grass privacy screen is the late-winter to early-summer gap. After the cut in late February or early March, the screen is gone until new growth fills in by mid to late June. That is roughly 8 to 12 weeks of bare ground, depending on the climate.
For some gardeners, this gap is acceptable. The screen is most needed in summer and fall when the garden is in use, and the bare stems in winter are a feature, not a bug, since they let light into the garden. For other gardeners, the gap is a deal-breaker, and they need a year-round screen.
The fix is to plant the grass screen in front of an evergreen backbone. A row of tall grasses in front of a yew hedge, an arborvitae row, or a fence gives the best of both worlds: the evergreens provide year-round screening, and the grasses add the movement, fall color, and summer density that the evergreens cannot match. The grasses also soften the formal look of the evergreens with their arching habit and fine texture.
For gardeners who cannot use evergreens, the grass screen alone is the right choice, with the gap accepted as part of the seasonal rhythm.
Care of the screen
The care routine is the same as for any ornamental grass: full sun, lean soil, no fertilizer, water only during establishment, leave the clumps standing through winter, cut in late winter.
Fertilizer is the worst thing to do for a screen. Rich, fertilized grass grows tall and floppy, and a screen that flops open in August is worse than no screen at all. The lean-soil approach produces tight, upright clumps that hold their form through summer.
The cut in late winter is the big task. For a screen of 12 to 15 large clumps, I use a hedge trimmer and a leaf rake. I tie each clump with twine about two-thirds of the way up, cut below the tie with the hedge trimmer, and carry the bundle to the compost pile. The whole job takes about an hour for a screen this size.
Dividing is needed every 3 to 5 years, when the centers of the clumps die out and the screen gets hollow in the middle. I divide in spring, lift the whole clump, discard the dead center, and replant the vigorous outer growth. Division rejuvenates the screen and gives me new plants to extend it.
When I moved into my current house in 2014, the property line on the east side was open to a neighbor’s elevated deck, about 8 feet (2.4 m) above grade. I needed a screen that would reach 8 feet by midsummer and hold through fall. I planted a staggered double row of 14 miscanthus ‘Gracillimus’ at 4-foot (120 cm) spacing, with the first row 2 feet (60 cm) in from the property line and the second row 4 feet (120 cm) behind. The first year the screen reached 5 feet (150 cm) and partially blocked the deck. By year three it was a continuous wall of 7-foot (2.1 m) grass with plumes that hit the deck railing. The screen was gone in early spring, but the neighbor’s deck was rarely used before June, so the gap was acceptable. Nine years out, the screen is the best feature of the garden. The miscanthus has been divided twice and shows no signs of decline.
The matching shrub option
For gardeners who want year-round privacy, the practical combination is a screen of evergreen shrubs with tall grasses planted in front. Arborvitae (Thuja occidentalis) at 6 to 8 feet (1.8-2.4 m) in the back row and miscanthus or switchgrass in the front row gives a 12-month screen with summer and fall interest.
Yew (Taxus x media) is another option for the evergreen backbone, though yew is slower to establish and more expensive. Yew behind miscanthus makes an elegant cold-climate screen, with the formal yew providing structure and the arching miscanthus adding movement.
The grasses in front of an evergreen backbone do not need to reach full height to do their job. A 5-foot (150 cm) miscanthus in front of a 6-foot (1.8 m) arborvitae gives a 6-foot screen from the property side and a 10-foot visual wall from the garden side. The evergreen handles the winter months, and the grass handles the summer months. Each does what it does best.
The non-seeding choice
Miscanthus has a self-seeding problem in mild climates. The fertile cultivars can produce viable seed that germinates in disturbed soil, and ‘Miscanthus sinensis’ is on invasive plant watch lists in more than half the eastern US states (USDA NRCS). For gardeners in those areas, sterile cultivars are the responsible choice.
’ Morning Light’, ‘Gracillimus’, ‘Adagio’, ‘Variegatus’, and most other popular cultivars are fertile and can self-seed. The sterile options include Miscanthus x giganteus (a sterile hybrid) and ‘NCMS2B’ (sold as ‘My Fair Maiden’), a fertile-sterile cultivar developed by the University of Georgia.
Big switchgrass (Panicum virgatum) also self-seeds, but the seedlings are easy to spot and remove. Unlike miscanthus, switchgrass is a native plant, so even its self-seeding does not create an invasive issue. The CBG Panicum virgatum trial documented modest self-seeding in some cultivars, with Shenandoah and Heavy Metal showing the lowest rates.
Ravenna grass (Saccharum ravennae) is generally sterile in cold climates, since the growing season is not long enough for the seed to mature. In zone 7 and warmer, it can produce viable seed. Gardeners in mild climates should check local invasive plant lists before planting it.
A short list for tall screening
For gardeners who want a simple, reliable screen:
- Miscanthus sinensis ‘Gracillimus’ for the showy 6-foot screen in zone 5b and warmer. Plant in a staggered double row 3 to 4 feet apart.
- Panicum virgatum ‘Cloud Nine’ for the native 7-foot screen in any cold climate. Plant in a staggered double row 3 to 4 feet apart.
- Saccharum ravennae for the tallest screen, reaching 8 to 12 feet in zone 5b and warmer. Plant in a single row 4 to 6 feet apart.
- Miscanthus x giganteus for the sterile 10-foot screen in zone 5b and warmer. Plant in a single row 3 to 4 feet apart.
All four need full sun and lean, well-drained soil. All four die back to the ground in winter and reshoot from the crown in late spring. The screen is at peak from July through February, with the bare-stem gap from March through June accepted as part of the trade-off.