Sedges (Carex spp.) are grass-like plants with a wide variety of landscaping applications. Like ornamental grasses, they have a tidy clumping habit and come in a variety of colors and forms.
Carex Essentials
Carex/Sedges may be difficult for the non-botanist to differentiate from grasses, although the leaves tend to be thicker and more serrated compared to most grasses. They produce tiny seed heads with little ornamental value, so the primary draw with sedges is their foliage, which tends to have a very uniform appearance through all four seasons with gracefully arching stems that form a pleasing texture in the landscape when planted en masse.
Important Characteristics
Many sedge varieties are available, but most fall with the eight to 16-inch range in both height and width and prefer to grow in full or part sun. They are adaptable to a wide range of soil conditions, and they tolerate both drought and dampness. These plants look their best in rich soil, but they grow satisfactorily in poor soil. Overall, sedges are very easy plants to cultivate.
Garden Design
Sedges are unmatched as a palette of texture and color in landscape design. Their colors range from nearly orange to buff to deep green to chartreuse to silver and almost blue, and they are an excellent choice where a soft and airy groundcover is desired over a large area. They are also an ideal groundcover around flowering trees.
One effective technique is to plant swaths of sedges of different sizes and colors interspersed with ornamental grasses for a layered effect. Sedges do not form a flat turf like lawn grasses do, but they can be used as a lawn alternative if a surface is not needed for recreational purposes. Sedges are often included as part of meadow plantings along with wildflowers.
Growing Sedges
Plant sedges in spring, summer, or fall and provide irrigation during dry periods for at least the first two years. They are typically planted from pots or as groundcover plugs on an eight to 16 inch spacing, depending on the mature size of the plant. Sedges do not need a large hole; simply excavate an area equal to the size of the root ball and put them in the ground.
Spreading Habit
Over time, sedges spread via underground rhizomes and create a solid, grassy groundcover which resembles a hummocky meadow. Fortunately, their rhizomes are very short, which keeps them from being an invasive nuisance in the landscape.
Care and Maintenance
Sedges are very low-maintenance plants. The primary chore required to keep them looking their best is to cut the foliage to within a few inches of the ground once per year. This can be accomplished in the fall, or the dead foliage can be incorporated as part of a winter garden and trimmed off in early spring. This practice encourages neat, tightly formed clumps and prevents the build up of an unsightly thatch layer.
Sedges are virtually free of pests and disease.
Common Sedge Varieties
Most common varieties of sedge are available in garden centers throughout the country.
Carex Variegata
'Blue Zinger' grows to 12 inches and has a blue cast to the foliage; USDA zones 4 to 8
'Everest' grows to about 10 inches tall and has white margins on the foliage; USDA zones 5 to 9
'Everillo' grows to 12 inches and has bright yellow foliage; USDA zone 5 to 9
'Variegata' grows to about 10 inches and has silvery grey foliage; USDA zones 4 to 8
Sedges Add a World of Texture
Sedges are so popular among landscape designers because they are easy to grow and are available in a tremendous array of colors. Used over large areas, they create a soft, billowy feel on the landscape, which makes a pleasing contrast to other types of plants. Consider adding a few sedges to your garden landscape and see how you like them.