The Role of Sedges in Garden Design
Sedges are a plant variety that possesses distinctive looks and hardiness. They are adaptable to a variety of site conditions and offer a trove of textures and colors that bring depth to your overall garden design. Until recently, sedge has been one of the most useful yet under-used garden plants according to Shannon Currey of Hoffman Nursery.
Although many garden plants are more beautiful than sedge, few are more functional. Currey says that sedge is the “workhorse plant” of the garden because it is active year-round.
When used as a groundcover instead of mulch, sedge not only suppresses weed growth but contributes organic matter to the soil. It provides shelter and food for beneficial insects and birds. And it looks really great while doing all that.
Landscape architect Howard Cohen says he likes to try different things and is always looking for alternative groundcover plants. He is a fan of sedges not only because of their versatility but because they come in so many different textures and colors. And, he says, “they’re hard to kill!” Deer don’t like to eat them.
You can plant them close together and let them fill in or space them out. They work well in planters where they grow tall and spill over the sides. I really like the Carex Evergold for that. Howard Cohen, Landscape Architect
Like Grass but Different
The sedge most popular in landscaping falls under the horticultural classification Carex. Like grasses, Carex grow in nearly every type environment and on every continent.
Unlike most grasses used in garden design, sedges are cool season plants. They bring vitality to the landscape at the seasonal edges when other plants are just emerging from or entering into dormancy. Sedges thrive in the cool weather of early spring, take a long siesta during summer while perennials flourish, then come back strong in late fall.
The sedges most used in garden design and landscaping are native North American species or imports from Asia. The Asian species are particularly colorful and work best in shady conditions.
Their fibrous, branching root systems help sedges to do exceptionally well in a range of different soil conditions. Both wet and dry. They are drought tolerant and low maintenance. Disease and pest issues are rare. Once established in the landscape, they don’t usually need supplemental irrigation. Sedges are incredibly versatile–these plants can grow where others can’t. For nearly every site condition, there is a sedge that will feel right at home there.
Adaptability-How to Use Sedges in Garden Design
They are filler plants primarily, but very pretty. This single species comes in so many colors and textures. Colors range from shades of green to bluish green to gold and amber. Howard Cohen, Landscape Architect
Sedges can play four primary roles in your garden design. They can perform as groundcovers, as an alternative to turf grass, as a base layer for beds that include mixed perennials and woody plants, or you can use them in container displays.
Sedges do well in shady spots, so they fill out nicely when planted around the base of a tree. Depending on the variety, they establish in either dry or moist soil.
2 Lawn Alternative
In low or no traffic areas, sedges provide a low maintenance alternative to turf grasses. They don’t require irrigation, fertilization, or regular mowing to stay healthy.
3 Foundation Layer
This use of sedge is known as matrix or “companion” planting. It’s been gaining popularity as landscapers attempt to conserve resources by designing more sustainable, self-sustaining gardens. Sedge serves as a foundation planting, or matrix, into which other plants are layered.
4 Container Displays
Sedges and grasses like well-drained soil, so do very well as container plants because containers naturally provide good drainage.
Artful use of sedges is far more appealing to behold than the vast swathes of mulch that tend to dominate landscapes in early spring and late fall while the showy superstar perennials are sleeping. Also, sedge provides valuable service to the overall garden design. It outcompetes weeds, contributes nutrients to the soil and provides shelter for beneficial organisms that boost the health of the garden. Even though they don’t show obvious flowers, many sedges are excellent pollinator plants because they provide nectar. Seed heads and foliage also provide food for pollinators and beneficials.
Popular Sedges Used in Garden Design
All images courtesy of Hoffman Nursery, Inc.
Ice Dance Sedge is a dense spreading sedge that grows up to 12″ tall. Its leaves are dark green in the center and white on the edges. It provides good coverage for woodland areas because of its habit of spreading rather than clumping.
Pennsylvania Sedge forms a velvety green carpet in shady conditions. Although it cannot handle foot traffic, it is an excellent visual substitute for turf grass. It’s a slow-growing creeper that will fill in over time.
Texas Sedge is a good turf substitute for dry to moist shade conditions. It produces a fine-textured and dense foliage that mixes well with other shade plants.
Red Rooster Sedge is an import from New Zealand and one of the few sun-loving sedges. It shows in orange-brown to red-brown and spreads in dense, fan shaped clumps. It produces tiny flowers in mid-summer.
Grassland Sedge grows in neat little mounds that look like grass. It makes a lovely deep green ground cover under established trees. It prefers dry shade, so offers a reliable solution for those tough spots where grass or other ground covers can’t survive.
If you’d like to dig deeper into what types of sedges are available for your landscape, we suggest reading “A Complete Guide to Sedges” by Hoffman Nursery. You may be surprised to see the wealth of distinctive characteristics coming from this one group of plants.
A Beautiful Solution to Rainwater Management
Some types of sedge species can tolerate inconsistent moisture conditions and are perfect for rain gardens and bio-retention sinks. These water management systems are required in many Virginia jurisdictions because they protect waterways from the pollution and erosion caused by storm surges.
Three sedges commonly used in rain gardens and bio-filtration sinks include:
Creek Sedge grows in compact, shaggy mounds presenting narrow, shiny leaves. It shows green flower clusters in late spring.
Tussock Sedge. This tufted wetland sedge that loves standing water or wet mucky soil. Leaves are bright green and spread fountain-like. Flower stalks shoot above the foliage in spring.
Cattail Sedge grows throughout the eastern states in wet meadows, flood plains, and forest edges. It forms small clumps of narrow, green foliage. Spikey, green seed heads pop up in late spring.
These native mid-Atlantic species occur naturally in marshes, floodplains, wet meadows, and along shorelines and woodland creeks.
Beauty & Utility
That’s what a great garden design should provide. The demand for grasses and “grass-like” garden plants in garden design is evidence that they captured the interest of designers and homeowners. Shannon Currey says this trend has developed for three reasons:
- Native plants have simply become more fashionable than they used to be
- There is a growing desire among homeowners and garden designers for landscapes that offer greater ecological function, that enhance human health and improve stormwater management
- The desire for more sustainable landscapes has driven a surge of interest in progressive garden design trends such as matrix planting that supports biodiversity
If you’d like to get more color, depth, and usability from your landscaping, contact one of our garden management specialists. Let’s trade garden design ideas!