How to Plant, Prune, and Grow Ornamental Grass
Up the “wow” factor in your garden by adding some ornamental grasses. The soothing sounds and hypnotic movement of these graceful plants on a breezy day add enjoyment to the garden, plus they are truly low-maintenance . See some of our top picks and learn how to plant ornamental grasses in this complete guide.
Types of Ornamental Grasses for Every Garden
I have grouped grasses into various categories to help you with your selection. Banish your mower and get to a garden center! Let the planting begin!
Note: Hardiness zones in this list are estimates. Growing conditions vary with each location. Check with your local garden center or Cooperative Extension to ensure a grass’s adaptability.
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*Not true grasses, but look and function like them
†Considered invasive in some areas
Grasses for Yellow Foliage
- ‘Aureola’ Japanese forest grass (Hakonechloa macra ‘Aureola’), Zones 5 to 8
- *‘Everillo’ Japanese sedge (Carex oshimensis ‘Everillo’), Zones 5 to 9
- *‘Ogon’ Japanese sweet flag (Acorus gramineus ‘Ogon’), Zones 5 to 9
Grasses for Blue Foliage
- Blue fescue (Festuca glauca), Zones 3 to 9
- †Blue lyme grass (Leymus arenarius), Zones 3 to 10
- Blue oat grass (Helictotrichon sempervirens), Zones 3 to 8
- *†‘Blue Zinger’ blue sedge (Carex flacca ‘Blue Zinger’), Zones 3 to 9
- ‘The Blues’ little bluestem (Schizachyrium scoparium ‘The Blues’), Zones 3 to 9
Grasses for Burgundy/Red Foliage
- †Purple fountain grass (Pennisetum setaceum ‘Rubrum’), Zones 9 to 11
- ‘Purple Majesty’ ornamental millet (Pennisetum glaucum ‘Purple Majesty’), all zones (annual)
- ‘Shenandoah’ switchgrass (Panicum virgatum ‘Shenandoah’), Zones 4 to 9
Tall Ornamental Grasses for Privacy
- †Giant reed (Arundo donax), Zones 6 to 10
- Giant silver grass (Miscanthus x giganteus), Zones 5 to 9
- †Maiden grass (Miscanthus sinensis ‘Gracillimus’), Zones 4 to 9
- †Pampas grass (Cortaderia selloana), Zones 6 to 11
- †Ravenna grass (Saccharum ravennae), Zones 5 to 9
Low Growing Grasses for Containers
- Blue fescue (Festuca glauca), Zones 3 to 9
- *Japanese sedge (Carex oshimensis), Zones 5 to 9
- *Japanese sweet flag (Acorus gramineus), Zones 5 to 9
- ‘Little Bunny’ Chinese pennisetum (Pennisetum alopecuroides ‘Little Bunny’), Zones 4 to 9
- Mexican feather grass (Nassella tenuissima), Zones 6 to 10
- Prairie dropseed (Sporobolus heterolepis), Zones 3 to 9
- †Purple fountain grass (Pennisetum setaceum ‘Rubrum’), Zones 9 to 11
- Ruby grass (Melinis nerviglumis), Zones 8 to 10
Ornamental Grasses for Shade
- Japanese forest grass (Hakonechloa macra), Zones 5 to 8
- *Japanese sedge (Carex oshimensis), Zones 5 to 9
- *Japanese sweet flag (Acorus gramineus), Zones 5 to 9
- *†Mondo grass (Ophiopogon japonicus), Zones 6 to 11
- †Northern sea oats (Chasmanthium latifolium), Zones 4 to 9
Grasses for Wet Soil
- *Japanese sedge (Carex oshimensis), Zones 5 to 9
- *Japanese sweet flag (Acorus gramineus), Zones 5 to 9
- †Maiden grass (Miscanthus sinensis ‘Gracillimus’), Zones 4 to 9
- †Northern sea oats (Chasmanthium latifolium), Zones 4 to 9
- Switchgrass (Panicum virgatum), Zones 4 to 9
Grasses for Dry Soil
- Blue fescue (Festuca glauca), Zones 3 to 9
- Blue grama grass (Bouteloua gracilis), Zones 3 to 10
- Blue oat grass (Helictotrichon sempervirens), Zones 3 to 8
- Mexican feather grass (Nassella tenuissima), Zones 6 to 10
- Pink muhly grass (Muhlenbergia capillaris), Zones 5 to 11
- Ruby grass (Melinis nerviglumis), Zones 8–10
Beware the Non-native, Invasive Grasses
Two of the most popular types of ornamental grasses are now considered invasive plants in many areas of the country.
- Steer clear of misbehaving Chinese miscanthus cultivars (Miscanthus sinensis). These exotics escaped cultivation, spreading via wind-blown seeds to invade and crowd out native plants. Some states have placed them on their invasive species lists. Switchgrass is a good native substitute.
- Many pennisetums including African fountaingrass (Pennisetum setaceum) and Chinese fountaingrass (P. alopecuroides) also have joined the naughty list. Even varieties sold as sterile have been able to cross with other cultivars and produce viable seeds. Try growing native prairie dropseed instead. Despite its name the seeds rarely germinate and they are a favorite food for birds and small critters.
Before adding any ornamental grass to your garden, check with your state extension service to see if it is invasive in your area.
Other grasses also come with a caveat. Although most behave themselves, others spread aggressively by seed or running roots, depending on location. Pampas grass (Cortaderia selloana), northern sea oats (Chasmanthium latifolium), ruby grass (Melinis nerviglumis), palm grass (Setaria palmifolia), and Chinese silver grass (Miscanthus sinensis) epitomize the former. Blue lyme grass (Leymus arenarius), variegated ribbon grass (Phalaris arundinacea ‘Picta’), and giant reed (Arundo donax) exemplify the latter. This doesn’t mean to not plant them; just be sure to consider their appropriateness for the site and watch for and control escapees.
About Ornamental Grass
Ornamental grasses stay attractive all season long and make striking accents or background plantings. They grow well into fall when many flowers are fading, and also add winter interest. See the best fall plants for your garden.
Grasses form cascades, mounds, and drifts; blend wonderfully with annuals, perennials, and shrubs; and sway in the breeze. Observes Charlotte, North Carolina garden designer Jay Sifford, “I love the kinetic quality of grasses as they flirt with the prevailing wind. A great garden nestles into and responds to the natural environment. Movement shows that.”
Unlike fussed-over lawns frequently derided as ecological deserts, ornamental grasses benefit wildlife. “Birds nibble on the seed heads,” says Sifford. “I’ve even seen hummingbirds swarm around the pink blooms of ‘Karley Rose’ pennisetum [Pennisetum orientale ‘Karley Rose’]. Grasses also provide shelter for small birds and beneficial insects.”
New York author and garden designer Jan Johnsen backs him up. “My favorite grass is our native prairie dropseed [Sporobolus heterolepis],” she reports. “In late summer, its brown-tinted, misty flowers on slender stems seem to float above the foliage. The birds love its seeds.” She extols native blue grama grass (Bouteloua gracilis) as well. More than 10 species of butterfly larvae dine on its foliage, and birds eat its seeds.
Sifford believes that “texture”—the interplay of varying shapes and sizes—is a vital asset that grasses bring to the garden that is often overlooked by the public in favor of bold splashes of color from bedding plants. This doesn’t mean that grasses lack color—far from it. Grass foliage can be blue, yellow, burgundy, striped, or variegated. Long-lasting blooms range from white to buff to copper, pink, and purple.
These low-maintenance plants come in a wide range of textures, forms, sizes, and colors. Scout out the boring, bare spots in your landscape that could use some four-season pizzazz.
Reasons to Plant
In addition to adorning mixed borders and meadows, ornamental grasses solve common problems. They slow the water in heavy rain and reduce erosion, an important consideration for sloping sites. Tall grasses screen unpleasant views and add privacy. Moisture-tolerant grasses are mainstays for rain gardens.
Graceful foliage and flowers of grasses also offer exciting opportunities in design. They bend and flutter with the wind and thus are well placed near bodies of water. Upright grasses such as feather reed grass (Calamagrostis x acutiflora) serve as superb vertical accents. Smaller grasses are perfect for pots. Arching grasses like Chinese pennisetum (Pennisetum alopecuroides) soften retaining walls and other hardscaping. Moreover, the aspect of grasses changes with the seasons. “In the fall, when the Sun is lower in the sky, tawny grasses seem to positively glow,” discerns Johnsen. “It is such a magical effect.”
Flowers to Plant with Ornamental Grasses
Perennials, especially those found in natural or planted meadows, make boon companions for grasses. Popular choices include such butterfly magnets as black-eyed Susans (Rudbeckia hirta; R. fulgida), purple coneflowers (Echinacea purpurea and hybrids), asters (Symphyotrichum spp.), butterfly weed (Asclepias tuberosa), daisies (Leucanthemum spp.), Joe Pye weed (Eutrochium purpureum), spike blazing star (Liatris spicata), and threadleaf coreopsis (Coreopsis verticillata).
Of course, every gardener has a favorite combination. Johnsen underplants vase-shape ‘Morning Light’ miscanthus with ‘Walker’s Low’ catmint (Nepeta x faassenii ‘Walker’s Low’) and ‘Caradonna’ violet sage (Salvia nemorosa ‘Caradonna’). “This grass’s slender, variegated foliage contrasts beautifully with the blue flowers of the others,” she notes.
Sifford extols the marriage of red-leaf ‘Shenandoah’ switchgrass (Panicum virgatum ‘Shenandoah’), the deep-pink blooms of ‘Magnus’ purple coneflower, and the orange and burgundy foliage of ‘Ginger Wine’ ninebark (Physocarpus opulifolius ‘Ginger Wine’). “Add a bit of ‘Blue Dune’ lyme grass, and you’ve created perfection,” he states.
In California, Santa Barbara landscape architect and writer Billy Goodnick touts small meadows mingling ‘Blue Zinger’ blue sedge (Carex flacca ‘Blue Zinger’), snow-in-summer (Cerastium tomentosum), ruby grass, Majorcan teucrium (Teucrium cossonii), and catmint.
Planting Ornamental Grasses
Ornamental grasses are easy to grow even for beginners and thrive from Canada to southern California and Florida. In general, they suffer few pests, don’t fret about the soil, and tolerate heat, cold, and drought. Most prefer sun, but others accept shade. Check hardiness zones to ensure that a grass you like is adapted to your area, remembering that variations in rainfall and humidity can make growing conditions vastly different from east to west, even if you’re in the same zone.
They are not too fussy about soil conditions. Though well-drained, fertile soil is optimum, they will thrive in poor soil, heavy clay, or dry sand and many are salt tolerant.
- When you plant your new grass, the crown should be slightly above the surface. Planting too low can rot the crown, too high and it will dry out.
- Space your plants far enough apart to allow for mature growth.
- Use mulch to control weeds and conserve moisture, but keep it 2” away from the crown. Bark mulch provides slow-release nutrients for the grass as it breaks down.
- Water thoroughly when planting and water deeply once a week during the first season while the plants get established.
- No fertilizer is necessary; it can actually weaken the plant by making the stems too tender and floppy. Compost is an acceptable supplement, but don’t use manure.
- Once plants are established they are drought-resistant and need additional watering only in the driest times. Overwatering causes more damage than underwatering - reducing flowering and even rotting the crown.
This is a truly low-care plant, no deadheading is needed. Most ornamental grasses are relatively pest and disease free.
Let the foliage stand in the garden all winter for movement and beauty. The lacy filigree of foliage and seedheads, when covered with frost and snow, is not only lovely to look at but provides food and shelter for the birds. The foliage acts as a natural mulch, protecting the crown against cold and ice.
How Do They Grow?
Ornamental grasses can be separated into two groups—runners and clumpers—based on their growth characteristics.
- Runners are spread by underground rhizomes or above-ground stolons. They make good ground covers, will crowd out weeds, and are perfect for holding soil in place on steep bankings. Strong runners can become an invasive nuisance though, overpowering other plantings.
- Clumpers are better behaved since they stay in one place. As the clump matures, it will get larger, but it won’t invade the rest of the garden, making it easier to design with.
When to Cut Back Ornamental Grass
Pruning is an annual requirement. When to do it depends on the grass. Cool-season grasses, as their name implies, grow in cool weather and go dormant in summer. Trim them in late winter and earliest spring. Warm-season grasses grow fast in summer and go dormant in fall and winter. Cut them to the ground when the foliage browns. This is particularly important in fire-prone areas, as brown, dry grasses ignite like Roman candles. Wear gloves because the sharp leaf edges can cause cuts.
As the clumps get older, they can die out in the center. Renew the plant by dividing and transplanting the new outer growth. Cut with a sharp spade or a knife; you may need to use a hatchet or an ax to divide tough clumps before digging them out. This operation is best performed in the spring.
Learn more about dividing perennials.
Ornamental grasses are truly four-season plants. Consider adding an ornamental grass or two to your garden for visual impact and winter interest.
Do you have any ornamentals in your landscaping? Share your favorite varieties with us below!
Steve Bender
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