Native grasses
Native grasses in your landscape
Native grasses are a great addition to any landscape plan, with many uses. Depending on the species, they can provide
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A strong structural element and textural variety
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Vertical accents
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Motion and sound (as the wind rustles through them)
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Winter interest (don’t cut them back until late winter)
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Screening (when grown densely)
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Resistance to deer browse
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Groundcover
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Nice addition to containers, whether you need a filler, thriller or spiller (but be careful as native grass roots grow really large and can overwhelm the container and crowd out other plants)
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Support to keep flowers from flopping.
Several grass species are notable primarily for their seed heads that often tower over shorter leaves, which are themselves unremarkable and serve as fillers. Others are grown specifically for their handsome clumps of leaves that provide a structural element to the garden. And a few are blessed with both attributes! Still others are ideal for the edges of water bodies.
Gardeners often cut back the foliage of grasses and sedges in late winter to create a clean look in the spring. Grasses can make a nice garden edging next to a walkway, but the short ones with fine leaves provide too little contrast if planted next to turf grass.
Choosing native grasses
The term “grasses” is often used loosely to include all the graminoids: grasses, sedges and rushes. All are monocots with long, narrow leaves and small flowers. There are exceptions (see below), but most grasses need sun and most sedges prefer shade, although some of the latter prefer sunny, wet conditions. To tell them apart, remember this saying: “Sedges have edges, rushes are round, grasses have joints that go straight to the ground.”
Grasses are designated as either “cool season” (European turf grass is an example) which do most of their growing in spring and late fall and require more water to stay green in the summer, or “warm season,” meaning they start to green up in late spring, grow the most in the summer when temperatures are between 75 and 90 degrees, and go dormant in the fall. A few grow like sod, but most of them grow in clumps, which makes for a lumpy lawn if grown for that purpose.
Some of the more notable species are highlighted below. There are many others. These were chosen because they are available locally for sale (some in conventional nurseries, others in specialty nurseries) and because they have features which are particularly attractive.
Native grasses in the ecosystem
Native grasses play a critical role in the ecosystem, providing
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Roots that are deeper than turf grass (which comes from Europe) and which do a better job at erosion control, breaking up hard soil and capturing stormwater
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Seeds, an important food source for birds and other wildlife
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Dense root structures that create a barrier to the spread of aggressive plants, creating pockets where more delicate plants can live
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Host plants for numerous species of butterflies, skippers, moths and others
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Nesting material and cover.
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Sequester carbon
Most of the plant material in a meadow consists of grasses.
Native grasses for lawn
In shady areas with minimal foot traffic, some native grasses can be used as a substitute for conventional lawns, though this would require planting a lot of little plants at 8-10 inch intervals and a good deal of attention during establishment, not just throwing down seed. Deep soil amendment is critical on a typical compacted former lawn area which lacks good nutrition and may have alkaline soil, and it can take a few years for such lawns to get established.
Grasses
Notable mostly for their interesting seed heads
Northern Sea Oats (Chasmanthium latifolium)
Clump-forming and upright, this grass is planted for its dangling seed heads and versatility. Large masses are popular in parking lot situations where it is quite tough. Can tolerate full sun with enough water but does better with more shade. Self seeds aggressively - sometimes in very undesirable ways - so keep it well isolated.
Bottlebrush Grass (Elymus hystrix)
Clump-forming
Virginia Wild Rye (Elymus virginicus)
Short grass with much taller seed heads which look like wheat. Self-seeds, and easily grown from seed. Clumping. Can crowd out Japanese Stilt-grass, which is quite a feat.
Warm season
Cool season
Cool season
Purple Love Grass (Eragrostis spectabilis)
When grown en masse, this very short, delicate grass creates a lovely purple cloud-like haze in late summer. In the late fall, the stems of the flowers fall off and blow in the wind like tumbleweeds.Reseeds. Space at 12 inches for a groundcover
Indian Grass (Sorghastrum nutans)
Arching green leaves in low tufts become pastel in fall. Tall showy flower stalks from midsummer into winter. Light straw color in winter, stays upright. Looks good in masses. May flop in rich soil. Can be an aggressive spreader. Space at 18 inches for a mass.
Warm season
Warm season
Purpletop (Tridens flavus)
Nice seed heads on top of low clumps show best in large masses.
Warm season
Grown primarily for their foliage
Broomsedge (Andropogon virginicus)
Attractive and large clump-forming grass turns a tawny brown in fall. Used as a structural element. Seeds are striking in fall and winter. Can be aggressive. This grass is allelopathic, meaning it excretes chemicals that impede the growth of some other plants. A very tough plant.
Warm season
Poverty Oat Grass (Danthonia spicata)
A very short grass for dry places, often used as a groundcover or possibly as a lawn replacement. Older leaves are retained and form curlicues. Shade tolerant but will not tolerate being shaded out by taller vegetation.
Cool season
Grown for both
Muhly Grass (Muhlenbergia capillaris)
Graceful arching clumps of fine foliage topped by a fantastic cloud of pink flowers in fall. If possible, plant so the sun will be behind the flowers. Must have good drainage - slopes are ideal - will not tolerate winter wetness. Clump forming. Best planted in the spring.
Switchgrass (Panicum virgatum)
Tall and very upright clumps topped by lacy seed heads, used as a structural element. Warm-season grass, turning golden in fall. Multiple cultivars available including 'Shenandoah' which reaches 4 feet and glows red when backlit and 'Northwind' which reaches 5 feet and stays upright. Best in full sun. Problematic in restoration settings where it has reduced biodiversity by crowding out other natives. In rich garden soil, it may also try to take over. Space at 24 inches for a mass.
Little Bluestem (Schizachyrium scoparium)
A particularly popular grass for gardens, very good structural plant with pretty seed heads and orangy fall color, upright and clump forming. Also looks good in a mass. Reseeds. Space at 12 inches for a mass.
Warm season
Warm season
Warm season
Grown in or near water
Giant Plumegrass (Saccharum giganteum)
May reach 10 feet with billowing plumes that open red then turn silver. Turns burgundy in autumn. Best planted in or near water.
Warm season
Woolgrass (Scirpus cyperinus)
Densely-tufted and clump-forming, this is technically a sedge, 4-6 feet high, with interesting wooly seed heads. Best grown in or next to water. Provides nesting habitat for wetland birds. Spreads slowly by rhizomes. Space at 18-24 inches for a mass.
Southern Wild Rice (Zizania aquatica )
Large sprays of small flowers produce rice. Best planted in or near water.
Warm season
Rushes
Common Rush (Juncus effusus)
Vase-shaped. Prefers moist or wet conditions but tolerates dry surprisingly well, though it may need watering during a drought. It’s natural environment is in or near water. Spreads by rhizomes (may be too much in some places) and self-seeding.
Juncus tenuis (Path Rush)
Juncus tenuis is a rush that is able to tolerate much more soil compaction and disturbance from walking or even driving than most sedges. Given its more erect habit it can be mowed periodically with no ill effect once established. Can tolerate a wide range of moisture and sunlight requirements making it the most robust option but less showy than many sedges. Semi-evergreen. Space at 10 inches for a groundcover.
Sedges
The choice of sedge in a landscape setting comes down to the function they will serve: 1) lawn replacement), 2) ground cover in semi-formal situations such as a replacement for liriope or 3) filler in conservation landscapes or rain gardens. They can be categorized by the width and color of the leaves and the overall size. The fine-textured ones when planted in a mass can give the appearance of turf grass. Several are similar in appearance to Liriope, and some of those are blue-green. Many are evergreen or at least semi-evergreen. Some thrive in very wet conditions including standing water and are used at the edge of ponds or in water gardens. From the standpoint of the ecosystem, most sedges are either woodland or wetland plants.
Fine textured leaves (similar to turf grass)
Appalachian Sedge (Carex appalachia)
Fine-textured, like turf grass, in short clumps arching over onto the ground. Tolerates very dense and very dry shade. Adaptable except does not tolerate poor drainage. Can be used as a lawn alternative. Space at 10 inches for a groundcover.
Pennsylvania Sedge (Carex pensylvanica)
Used as a mass planting, it spreads by rhizomes to eventually fill in the gaps for one continuous mat. Can be mowed if you like (no less than 3 inches) but it does not like to be walked on. It does not grow well from seed. Space at 10 inches for a groundcover.
Eastern Star Sedge(Carex radiata)
Semi-evergreen clumps. Can be planted right at the base of shade trees though grows faster in part sun. Prefers it moist or wet. Fine-textured. Space at 10 inches for a groundcover.
Rosy Sedge (Carex rosea)
Similar to but slightly larger than Carex radiata. Graceful, thick clumps of fine-textured but relatively long foliage. Drought tolerant. Evergreen.
Tussock Sedge (Carex stricta)
A large clumping sedge with fountains of narrow leaves that prefers moist to wet soils and naturally forms hummocks in standing water, but which also can grow away from bodies of water as long as adequate moisture is provided. Spreads via rhizomes. Propagate by division of clumps every few years. Use as a border to ponds and along stream banks as a groundcover. Nice vertical element for the garden. This is only one of many sedges that are found in marshes and are suitable for wet areas or the edge of ponds. Space at 12 inches for a groundcover.
Medium width leaves
Eastern Narrowleaf Sedge (Carex amphibola)
Semi-evergreen, semi-erect clumps with medium width leaves. Will tolerate more sun if kept moist. Space at 12 inches for a groundcover.
Wood Sedge (Carex blanda)
A large sedge, Carex blanda is one of the most common sedges in various woodland settings around here. Medium width leaves and a pale color make it stand out. Integrates well with ferns, violets, wood phlox, and other low-growing and low-maintenance options. Semi evergreen. Excellent substitute for Liriope. Spreads by rhizomes. Tolerates alkaline soil. Substitutes for Liriope. Tolerates very dense and very dry shade. Space at 10 inches for a groundcover.
Blue Wood Sedge (Carex glaucodea)
Fine-textured, like turf grass, in short clumps arching over onto the ground. Tolerates very dense and very dry shade. Adaptable except does not tolerate poor drainage. Can be used as a lawn alternative. Space at 10 inches for a groundcover.
Gray’s Sedge (Carex grayi )
Evergreen, upright clumps with medium-width leaves and interesting mace-shaped seed heads. Naturally grows in or next to water and can tolerate full sun with enough moisture.
Spreading Sedge (Carex laxiculmis)
Blue-green, semi-evergreen clumps. Mass as a ground cover or an edging for paths or woodland areas. A good substitute for Liriope.Tolerates wet and requires some moisture. Spreads very slowly by rhizomes. Space at 12 inches for a groundcover. A good choice for rain gardens.
Wide leaves
Plantain-leaved Sedge (Carex plantaginea)
Wide, puckered leaves in semi-evergreen clumps make it particularly ornamental. Excellent substitute for liriope though needs at least a little moisture. Prefers at least a little shade. Typically used in a mass planting. Space at 10 inches for a groundcover.
Broadleaf Sedge (Carex platyphylla )
Similar to Carex plantaginea but smooth wide leaves instead of puckered, bluish in color and more tolerant of dry conditions once established (but keep watered until then). Naturally found in alkaline soils. Space at 10 inches for a groundcover. Evergreen.
Not actually a grass!
Blue-eyed Grass (Sisyrinchium angustifolium)
Great substitute for Liriope in sun. Forms big clumps. Although grass-like, it is a miniature member of the iris family. Like iris, they should be divided every two years. Avoid heavy mulch. Reseeds and can form thick stands over time.
