Sustainable Landscaping in the Suburbs
An inspiring project outside of Portland, Oregon, illustrates the potential for transforming suburban lawns into biodiverse sustainable landscapes.
According to a recent study conducted for NASA, lawns take up more surface area than any irrigated crop. To keep them the way we like them—manicured and green—the nation’s 32 million acres of lawn require lots of coddling in the form of irrigation water, fertilizers and pesticides.
But attitudes toward that verdant, uniform swath of green are starting to change, thanks to heightened interest in growing food and growing awareness of the importance of creating “backyard habitat” for pollinators, birds and other creatures, along with concerns about the rising cost (and availability) of water.
A case study in the suburbs of Portland, Oregon, shows the potential for suburban yards everywhere. This ¾-acre site, which had been previously dominated by large expanses of lawn and non-native ornamental plants, has been completely transformed into a dynamic landscape that not only helps to feed the homeowner’s family, but also provides habitat for birds, bees, insects, butterflies and other pollinators.
The site had its challenges, including a fairly steep grade and a sinkhole that contained debris from an old chimney. The front of the house was exposed to the street, where construction on a new development was about to begin. There were a few existing trees, but most of the planted area was lawn and non-native ornamentals.
Stone and vegetation work together to create a landscape that is both stimulating and calm. Over 1,000 plants were planted to replace lawn areas.
The Figure Ground Studio worked in collaboration with Fiddlehead LLC and clients Mark and Jeanette Swafford to turn this humdrum suburban landscape into an Audubon-Certified Backyard Habitat. Pete Wilson’s stonework helps tie the many elements of the landscape together.
The transformed landscape includes edible gardens, meandering paths, a firepit, a children’s garden, a small orchard and a rain garden for treating stormwater. It also includes whimsical touches, such as a ring of boulders for children’s play, and a “moon garden” with gray-leaved and white-flowered plants that glow in the moonlight.
Below, we’ll break down the elements of the Swaffords’ makeover. Most of these solutions can be implemented on any scale, so you’ll be sure to find strategies for your next sustainable landscaping project.
A Permaculture Approach
Opportunities for quiet contemplation are built into the landscape; for example, the stone seating at the edge of the “moon garden.”
Mimicking natural ecosystems can help create low-maintenance landscapes that achieve several goals at once.
The Swafford project is a good example of permaculture design principles in action. “We really tried to ‘stack’ functions, so features perform more than one task,” says Erin Muir, principal at The Figure Ground Studio. Permaculture is the practice of emulating natural ecosystems by closely observing them. Permaculture-inspired designs are naturally self-sustaining. They don’t require outside inputs of fertilizers, pesticides, or even supplemental irrigation. Nothing is wasted; in fact, waste is seen as a resource.
Here are some of the permaculture principles implemented in the Swafford project, which can be easily incorporated into any landscaping project:
This principle recognizes that natural features in a landscape rarely do just one thing. For example, the stonework planters in the Swafford landscape serve as containers for plants, but the terraces also interrupt and slow stormwater flows. Stonemason Pete Wilson also designed in places for people to sit. Similarly, flowering plants help stabilize slopes, mitigate rainwater, produce food for people, attract and feed native and naturalized pollinators and other wildlife, and add beauty.
If the home is the center of the design, zones are the concentric circles that radiate outward from that center. This practical principle recognizes an essential fact of human nature: We’re much more likely to take care of something if it’s close by. Therefore, vegetable and herb gardens that may be used frequently (and that may require daily care) are located as close to the house as possible. Lower-maintenance perennials are located farther away.
Design for Diversity
Following Muir’s planting design, Fiddlehead LLC installed over 1,000 plants to replace the lawn. The Swafford site plan shows very little empty space. The differing heights of plants provide structure in the landscape and offer more opportunities for birds and other creatures to take cover and build nests. Diversity and redundancy ensure that if one plant fails, something else will likely take its place, and also ward against the takeover by a single invasive species.
“When you have a mature ecosystem that includes trees, which creates shade, it naturally prevents weeds,” says Dave Barmon, co-owner of Fiddlehead LLC.
Going Native (and Naturalized)
A perennial “stroll garden” was planted with both medicinal plants and those that attract and nourish birds and bees.
Plants, shrubs and trees adapted to the region are more likely to thrive without outside inputs, including irrigation water.
From the beginning, the Swaffords conceived of their project as one with ecological landscaping goals. Midway through they decided these goals dovetailed with those promoted in their region’s Backyard Habitat Program. This voluntary certification program lays out specific guidelines for removing invasive species, planting natives, reducing pesticide use and creating wildlife habitat.
Native and native-adapted plants generally require little maintenance once established. Natives resist diseases and are more tolerant of droughts, storms and temperature swings. These plants evolved with specific soil conditions, including pH, bacteria and fungi associations, and beneficial insects; planting them creates a self-sustaining positive feedback loop. Native plants can even be used to remove contaminants from the soil, a process known as phytoremediation.
It’s still important to choose favorable locations for specific plants; for example, ferns are more shade tolerant. And the soil should be conditioned, if necessary.
There’s another important reason to plant natives. According to the National Park Service, 25 percent of North American native plants are at risk of extinction. Planting natives adds to the nation’s “genetic database” and helps creates patches of habitat for wildlife.
When enhancing a landscape for wildlife, make sure the design includes all of the elements of good habitat.
Birds, bees, insects and other wildlife need more than food to thrive. High-quality habitat includes food, water, cover and places for nesting and raising young. To support pollinators, this means making sure there are food plants throughout the year.
Wildlife water features in the Swaffords’ garden include strategically placed concave boulders. The depressions catch water, which is then available for birds, butterflies and bees. It’s also important to provide food for insects in different stages—for example, host plants for caterpillars as well as nectar plants for butterflies. In the Swafford project, these caterpillar-friendly plants include milkweed, elderberry and native rhododendrons.
The different layers—tree, shrub and groundcover—create structure in the landscape that supports wildlife.
“We also left dead snags and logs, which provide habitat,” says Muir. Leaving slightly “wild” edges benefits wildlife, but you can also enhance the landscape with nest boxes for birds, bats and insects.
Certified for Wildlife
The National Wildlife Federation (NWF) and National Audubon Society offer programs through which can certify your property, large or small, as wildlife habitat. The NWF Garden for Wildlife Program (formerly called the Backyard Habitat Program) requires the property owner to evaluate his or her own property. Once you fill out the required forms and pay a fee, you receive your certificate and a sign for your yard. The Audubon program is administered by various regional chapters, sometimes in conjunction with other partners. Each one is a little different; for example, the Swaffords participated in the Certified Backyard Habitat Program in the Portland, Oregon, area. A collaborative effort between the Audubon Society of Portland and the Columbia Land Trust, the program has five elements: invasive weed removal, native plants, pesticide reduction, stormwater management and wildlife stewardship. A qualified technician evaluates the property, helping identify invasive weeds and making recommendations that are right for the specific property and fit with other landscaping goals.
Why certify? Enrollment in programs can potentially help researchers track their impact on certain species, such as monarch butterflies. The signs can generate interest from neighbors, who might be inspired to create habitat in their yards, too. In the case of the NWF program, proceeds go toward increasing declining habitat for bees, birds and wildlife.
Audubon Programs: Contact your nearest regional chapter
NWF Certified Wildlife Habitat Program
Working with Water
Several strategies work together to slow the flow in this suburban landscape. Stormwater management was an important goal for the Swaffords’ steep site.
“We tried to slow the flow in a couple of ways,” says Muir. The strategies include capturing and directing stormwater, infiltration features and pervious hardscaping, which work together to ensure stormwater is treated by plants and soil (and recharges groundwater) rather than carrying sediment and pollutants to the creek that flows to the northwest of the property.
Slough Sedge (Carex obnupta)—a clumping grass-like native that can handle having “wet feet”—was planted along the porch to intercept overland flow. Simply replacing the large swaths of lawn with a mixture of plants of varying heights helped intercept water and improves infiltration. The stepped gardens interrupt the flow of stormwater, while making the site more walkable.
Food for People
Food-growing can be easily integrated into suburban and urban landscapes.
The Swaffords’ landscape design incorporates several opportunities for growing food. The home orchard replaced a sloping lawn that was hard to traverse. It includes figs, apples, persimmon and pawpaw, a North American native that produces oblong yellow fruit that tastes a little bit like mango crossed with banana. Some older fruit trees, including an apple and a plum, were retained. Blueberry bushes and raspberries round out the orchard.
“Because it was a sloped site, we seeded a native plant mix under the orchard,” says Muir. These plants helped stabilize the soil and fix nitrogen. Today, a path winds through the orchard to allow for ease of plant care, harvest and enjoyment.
“Food security is important, but people should grow food because they enjoy it,” says Dave Barmon, co-owner of Fiddlehead LLC.
The vegetable and food gardens are strategically located close to the house. A central vegetable plot serves as a flexible space, depending on the family’s available time for gardening. One year, it was planted with a variety of veggies; the next year, it was planted with a cover of mint.
Tips for Home OrchardsVisions of baskets full of fruit often compel homeowners to buy inexpensive bare-root fruit trees during the first sunny days of early spring. But it’s far better to proceed with caution. Share these tips with your clients to help them design a home orchard that’s a good match for their skills and, more importantly, their time and energy.
Keep records. You might think you’ll remember what varieties you’ve planted, but years down the road, you will be grateful to have a record of what worked and what didn’t.