Success with Sedges

Native sedges ( spp.) are growing in popularity as adaptable, low-care landscape

with hidden talents. ARTICLE AND PHOTOGRAPHS BY KAREN BUSSOLINI

F WE ARE to create more sustain- able, environmentally beneficial I landscapes, choosing native plants already adapted to habitats where we live is a good place to start. Native sedges (Carex spp.) are a perfect illustration of this philosophy. Most of us have proba- bly unknowingly tromped on hundreds of these ubiquitous grasslike plants while hiking or walking in natural areas. I cer- tainly have, because now that I’m aware of them, I spot them all over the woods around my home. In my own garden, and in my role as a garden coach helping people learn to care for their yards, I expect plants to function, not just sit there looking pretty. I see no reason why every we use can’t be beautiful, support wildlife, and solve prob- lems, too. Sedges, I’ve come to realize, fill The author uses plantainleaf sedge (Carex plantaginea), shown here as an accent for woodland phlox, in her Connecticut wildflower garden. all kinds of tricky niches in a landscape. They hold stream banks, populate mead- are relatively few generalists.” Fortunate- age browns out in winter, cut it back early, ly available. Its native habitat ranges from ows, prairies, wetlands (and rain gardens), ly for gardeners, life is easier in cultivated before blooms appear. Cutting them back through eastern North Amer- carpet dry woodlands, tuft rocky slopes, landscapes, where many readily later may make for neater form, but you ica in a narrow deciduous forest niche replace lawns, weave their way through adapt to a wider array of growing condi- sacrifice seeds. with rich, moist, neutral to alkaline soils. paving stones, suppress weeds, and feed tions than they do in the wild. Before moving on to profiles of some In the garden, though, this broad-leafed, and shelter wildlife (see sidebar, page 26). individual sedges, I should point out that clump-forming beauty thrives in light to And their quiet beauty belies their tough NUTS AND BOLTS it can sometimes be difficult to find retail deep shade, tolerates relatively acidic to nature and adaptability. Sedges usually have solid, triangular sources for these wonderful plants. Ma- alkaline soils and moist to somewhat dry Sedges (Carex spp.) are part of the large stems and leaves arranged around the ny are available only “to the trade” from conditions. Its medium to dark green, and diverse sedge family (). Of stem pointing in three directions. If you wholesale nurseries or those that specialize semi-shiny, half- to three-quarter-inch- the estimated 2,000 species in the genus took a botany class, you may recall their in providing large orders for plant resto- wide, deeply puckered leaves suggest its worldwide, some 500 are native to North stem structure distinguishes them from rations, so you may need to ask a local other common name—seersucker sedge. America. Confusingly, botanists tend to re- true grasses have round, often hollow nursery to order for you. Some species Adding to its showiness are the thin deep fer to all members of the family as “sedges,” stems, with swollen joints. will be available at local native plant sales purple, nearly black-tipped flowers that so you’ll sometimes see Carex species distin- In habit, this diverse genus is quite vari- and in specialty nurseries. You can also emerge in early spring. guished as “true” sedges. able. They can be neatly clump-forming order cost-effective plugs and bareroot Plantainleaf sedge is striking as a spec- “Nearly every North American habi- or aggressively rhizomatous, short and plants from a few mailorder nurseries (see imen or as a low, bold-textured (and tat hosts sedges, often multiple species,” fine-textured or big bold and wide-bladed, “Sources,” page 29). weed-suppressing) mass. It plays well says sedge expert Robert Naczi, the Arthur with flowers and seed heads that run the with others. Michael Hagan, curator of J. Cronquist Curator of North American gamut from those that are easy-to-overlook SEDGES FOR SHADE the NYGB Native Plant Garden, likes Botany at the Botanical Gar- to eye-catching species bearing showy bris- A favorite of many gardeners is the how its tidy foot-tall clumps make room den (NYBG). “Although some sedges have tles or capsules. Native sedges generally stay tricky-to-propagate plantainleaf sedge for trilliums and other woodland wild- Designer Ana Hajduk of Singing Brook Garden in Wassaic, New York, massed ‘Oehme’, a variegated large ranges,” he explains, “they tend to be green throughout the winter and bloom (C. plantaginea, USDA Hardiness Zones flowers. I accent a sweep of woodland selection of palm sedge (Carex muskingunensis) as groundcover under this birch tree. very specific to niches and habitat—there from early spring to early summer. If foli- 5–8), which thankfully is now more wide- phlox (Phlox stolonifera) with scattered

24 the American Gardener July / August 2020 25 clumps and combine it with Canada gin- persist into winter and are attractive either ger (Asarum canadense) and fine-textured in the garden or in cut flower arrangements. sedge (C. pensylvanica, Gray’s sedge grows in slightly shaggy Zones 4–8) for contrast. clumps along creek edges, in wet decidu- Delicate-looking Pennsylvania sedge, aka ous forests, sandy swamps, marshes, and oak sedge, is irresistibly graceful in its own wet prairies throughout eastern and cen- right, and also tough as nails. This eight- to tral North America. Growing in acidic to 12-inch rhizomatous spreader ranges across moderately alkaline soils in full sun to part eastern North America into the Midwest. shade, it can take temporary flooding, but It grows sparsely in dry upland woods with does not tolerate dry soil. acidic soils, mingling with wild geraniums Its lime-green, half-inch-wide, pleated (Geranium maculatum), lowbush blueber- leaves grow in upright, one- to two-and- ries, and woodland asters. In the north, as- a-half-foot-tall clumps arching over on suming ample moisture, it tolerates more top. It spreads slowly, beautifully controls sun than in its southern range. erosion, thrives in problem wet spots, and As an eco-friendly lawn alternative, works well naturalized in large sweeps, as Pennsylvania sedge’s low height, unifor- an accent, or even in containers. mity and lovely fine texture give a soft, I was initially surprised to see this undulating “lawn look” in low foot-traffic water-lover luxuriating in gardens below areas. I value it as a good-natured mingler tall exposed ledges at the Coastal and weaver that threads its way through Botanical Garden in Boothbay. The stony crevices too narrow to plant. spine of land above was dry and sunny, with soil barely painted into crevices. But SOME LIKE IT WET rainwater sheeting down these impervious Taller-growing sedges suitable for wet rocks soaks into porous soil contoured to sites abound. Among these is palm capture runoff, which made conditions sedge (C. muskingumensis, Zones 4–9), a just right for Gray’s sedge. curvy, cold-hardy midwesterner native to floodplain forests and wooded lowlands. LAWN SUBSTITUTES IN WARMER REGIONS Among its kin, palm sedge stands out as At the Coastal Maine Botanical Garden in Boothbay, clumps of Amsonia hubrichtii in spring bloom Another important role for sedges is as an exotic-looking showstopper, growing punctuate a carpet of fine-textured Pennsylvania sedge (Carex pensylvanica). lawn substitutes, particularly in hot or two to three feet tall. Its eight- to 10-inch, drought-prone regions. Native sedges for densely arranged, glossy, bright green shade, where it expands gradually to form hollies (Ilex verticillata) and shadblows lawns must be low-growing, need little pointed leaves radiate around the stems, a weed-suppressing colony. Plant it around (Amelanchier canadensis) in a wet, sunny or no mowing, spread rhizomatously, giving the appearance of pinnate palm trees or leggy understory shrubs for a visually spot. Its clumping habit accommodates flourish without supplemental fertilizers, fronds. The flowers aren’t showy, but they exciting underplanting that gets going early Camassia leichtlinii ‘Blue Danube’, cre- be adaptable, drought and/or moisture rise above the foliage, ripening into spike- in the season, or combine with Joe Pye weed ating a gorgeous blue/gold combo that tolerant, climate appropriate, and—most lets of buff-colored seeds. (Eutrochium spp.) near water. I’ve further enhanced with golden Alex- important—tolerate some foot traffic Palm sedge is a good replacement for In my yard, ‘Oehme’, a golden varie- anders (Zizia aurea). Palm sedge isn’t without wimping out. invasive dwarf bamboo in moist semi- gated cultivar, knits together winterberry just a pretty companion, though. Its Andrea DeLong-Amaya, director of hor- ticulture at the Lady Bird Johnson Wild- flower Center (LBJWC) in Austin, Texas, PLANT SEDGES FOR WILDLIFE Gray’s sedge (Carex grayi)—here with spiky seedheads—makes a bold accent for moist sites. praises the local heat-tolerant sand sedge, Landscapes are infinitely more beneficial—and interesting—when you take into account how well the plants you choose sometimes called the Texas Hill Country support the entire life cycle of insects, birds, and other wildlife. unpalatable-to-deer foliage seems to dis- The sunnier the location, the more moisture sedge (C. perdentata, Zones 7–10): “It’s Sedges are larval food plants for many moth and butterfly species. University of entomologist and book author courage camassia munching, it grows tall it needs. It can even grow in a couple inches bright green, really pretty, and lush. I could Douglas Tallamy has identified 36 mid-Atlantic Lepidoptera species that feed on Pennsylvania sedge (Carex pensylvanica), enough to conceal camassia’s sprawling of water, making it ideal for pond edges, rain see it as a lawn if you like the soft, mounded spreading sedge (C. laxiculmis), tussock sedge (C. stricta), and fox sedge (C. vulpinoidea). Other notable caterpillar-feeding after-bloom foliage, doesn’t complain gardens, bioswales, and water gardens. look.” California-based grass expert John species include seersucker sedge (C. plantaginea), clustered field sedge (C. praegracilis), and palm sedge (C. muskingumensis). when it doesn’t rain, and turns an attrac- Semi-evergreen Gray’s sedge (C. grayi, Greenlee recommends it as growing well in Energy-rich sedge seeds feed many mammals and birds—at least 29 bird species, according to a list provided on the tive yellow in fall. Zones 3–9), also called morningstar or bur sun or shade, and heavy or sandy soils. He Wildflowers website (see “Resources,” page 29). Small songbirds eat tiny seeds of woodland sedges; upland birds, Although its natural niche tends to be sedge, stands out as an ornamental with writes, “It looks best when watered regularly, such as grouse, woodcock, and wild turkeys, consume larger seeds. Tall wetland sedges, many with seeds that float, are an sites with wet, neutral soils and dappled spiky flowers and unusual star-shaped but like most sedges, it will tolerate periods important source of sustenance for waterfowl. shade, palm sedge is not fussy about pH, seedheads that some references describe of summer drought.” Sedges also create vital habitat and cover for a wide range of animals. Clumping sedges are nest sites for ground-nesting birds, grows well in moderately fertile, loamy gar- as “mace-like,” although I think they are Horticulturist Julie Marcus, also at the and native bees excavate brood chambers in the soil below. Sedges provide protective cover for birds, amphibians, and small mam- den soil—even clay—and tolerates a wide much prettier than that medieval weapon. LBJWC, recommends Texas sedge (C. mals. Taller aquatic species are cover and nesting sites for waterfowl, and shelter mating amphibians. —K.B. range of light exposure. If it flops in deep These seedheads, greenish-yellow at first texensis, Zones 5–9) for dry shade in well- shade, cut it back; the foliage quickly renews. and then gradually turning brown, often drained caliche soils under junipers in the

26 the American Gardener July / August 2020 27 MORE REGIONALLY ADAPTED SEDGES TO CONSIDER Sources Plant Name Height/Width Characteristics and Site Requirements Native Origin USDA Hardiness Greenlee and Associates, Brisbane, (inches) Zones CA. www.greenleeandassociates. Carex amphibola 8–12/8–12 Forms compact upright mound of bold foliage; Eastern North 3–9 com. (Note there is a $500 mini- (creek sedge) moist shade America mum order.) C. appalachica 12/10 Clump-former with fine-textured foliage; Eastern North 3–8 Prairie Moon Nursery, Winona, MN. (Appalachian sedge) tolerant of dry shade America www.prairiemoon.com. C. cherokeensis 12–18/18–24 Forms groundcover; moist soils in part sun to Southeastern U.S. 6–9 Prairie Nursery, Westfield, WI. (Cherokee sedge) full shade www.prairienursery.com. C. eburnea (bristleleaf 8–8/6–8 Tufts of fine foliage spread slowly to form Central and eastern 3–8 or ivory sedge) groundcover; thrives in dry, alkaline soils North America Resources C. vulpinoidea 12–36/6–24 Clumps of arching, fine-textured foliage spread Widespread North 3–8 The Encyclopedia of Grasses for (fox sedge) slowly; moist to seasonally dry sites in part America Livable Landscapes by Rick Darke, shade to sun Timber Press, Portland, OR, 2007. The Illinois Wildflowers, Southwest. This wide-ranging sedge also they don’t mind if the tops are burned, tell apart, which means they are frequent- www.illinoiswildflowers.info/grasses/ tolerates hot, humid southeastern sum- and the nutrient load from ash that sifts ly misidentified or mislabeled. Clustered tables/table6.html. (This site lists mers. It forms three- to four-inch mats down is like a fertilizer shot,” he says. field sedge, is more readily available for birds fed by Carex seeds.) that can either be left unmown or cut a In Reed’s experience, two sedges excel home gardeners. Planting in a Post-Wild World by couple times a year for a neater look. as lawns in California. They are sand dune According to Reed, both are adapted Thomas Ranier and Claudia West, Bruce Reed, horticulturist at the Santa or meadow sedge (C. pansa, Zones 6–9), to long, dry summers and are rambunc- Timber Press, Portland, OR, 2015. Barbara Botanic Garden in California, re- from West Coast beach habitats, and clus- tious runners that can become weeding ports that after 75 percent of the gardens tered field sedge (C. praegracilis, Zones problems in garden beds. “How much burned in a wildfire, native sedges, adapt- 5–8), which grows throughout western water you provide depends on how lush the beginning, it will keep sending new ed to a fire ecology, came back beautifully. and central North America, even in high you want them to look,” he says. “Once growth out from the base.” “So much of their life is in the , desert areas. The two species are hard to established, even in southern California, PROMISING FUTURE Landscape designer and author Claudia West, who is one of the principals at Phy- to Studio, a landscape architecture firm in Washington, D.C., views sedges as one of those plants that play a key role in sustain- able landscapes. “We need to move away from mulch and fill gaps in the landscape with plants to provide habitat and hold the soil,” she says. “Sedges provide essen- tial soil-building function and support wildlife. They may not be the showiest, but many are evergreen, so you see them in winter, green, lush and gorgeous.” The adaptability, usefulness, and beauty evident in what is currently only a handful of commonly available native sedges hints at the potential in this genus. “When people Drought- and heat-tolerant sand dune or meadow sedge (Carex pansa) is widely used as a catch on to the diversity of colors, growth lawn substitute in California, as shown in this courtyard in Santa Barbara. forms, and growing conditions, they will embrace them in a big way,” Naczi predicts. you can water once every 10 days or twice in weed-free, prepared ground and keep “Any place you’d want to grow a plant, a month and maintain modest growth weeding and watering regularly until the whether it’s sunny or shady, wet or dry, or and green all summer. They will stay put sedge is established. The decision to mow the soil is acidic or alkaline, there’s a sedge if it’s dry, but will always seek out water; the lawn or let it grow naturally needs to for every spot.” m if there’s a source nearby they’ll run to- be made at the start. “If you let it reach its ward it.” full height, it’s difficult to mow, and the Karen Bussolini is a photographer, writer, When using sedges as lawn substi- cut stems, which are slow to break new speaker, and eco-friendly garden coach based tutes, the expense and effort are all up buds, will remain brown,” says Reed. in South Kent, Connecticut. You can view

Adaptable Texas sedge (Carex texensis) serves as a turfgrass replacement in this area of lawn at the Lady Bird Johnson Wildflower Center in Austin. SAXON HOLT front. Plant plugs six to 12 inches apart “But if you train it to be mown from her work at www.karenbussolini.com.

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