Pachysandra terminalis and Thymus citriodorus make for great Pacific Northwest ground covers.
A garden display at the Elisabeth C. Miller Botanical Garden in Seattle, Washington Photo by Richie Steffen
The concept of designed plant communities combines the synergy of nature with the order and beauty of horticulture
Some neighbors are better than others. They’ll take in your mail, watch your dog or bring you soup when you’re sick. Then there are those who fight over boundaries or play their music at 2 a.m.
So it is in gardens. Designed without thought to neighborly compatibility, plants won’t thrive without an unsustainable amount of effort.
But combined in designed plant communities — a term coined by Claudia West and Thomas Rainer in their book “Planting in a Post-Wild World” — plants can work together as friends.
In the book, West wrote about the approach as a hybrid between the wild and the cultivated, what she calls a “new nature” that can flourish in cities and suburbs but needs the help of humans.
Designing gardens this way is an interpretation of nature, not an imitation, West said in an interview. Their approach is not about restoring ecosystems — though plant communities call out to pollinators and other wildlife — but rather looking to nature, observing what grows together and designing a creation for the human eye. It’s not a science, but a philosophy — one that’s attracting interest.
“Designing with plant communities cannot only link nature to our landscapes, but also bring together ecological planting and traditional horticulture,” West and Rainer stated.
Three layers of plants make a complex community. By Claudia West
Greater than the sum
Mulysa Melco, owner of Resilience Design in Portland, Oregon, gets the concept. “The whole is greater than the sum of its parts.”
Melco’s designs link her love of nature, where she gets her inspiration, and her goal to give clients a low-input garden that appeals to their aesthetic. In her own garden, she’s created a community around an English walnut with species that can take its inclination to suppress a majority of plants because of the allelopathic chemical it releases.
Instead of fighting the tree, Melco planted species unaffected by juglone. She put in native plants like wild rose, creeping Oregon grape, sword fern, knick-knick, broadleaf stonecrop and lots of berries, including artic strawberry as a ground cover. Now, the neighboring plants work together rather than fight the site.
Though in this instance natives were the appropriate choice, West and Melco steer people to non-natives, as well. A native-based design is a good place to start, but if a plant fits and isn’t invasive, it’s acceptable — even desirable.
“By focusing on naturally occurring plant communities as opposed to those that are purely native, the focus is shifted from a plant’s country of origin to its performance and adaptability,” West and Rainier wrote in their book. “The shift is absolutely crucial … we must put aside our romantic notions of pristine wilderness and embrace a new nature that is largely designed and managed by us.”
Gymnocarpium dryopteris ‘Plumosum’, and Blechnum penna-marina. Photo by Richie Steffen
The plantings have the “spirit” of wild spaces that still speak to people but are created to appeal to modern sensibilities that want more ordered landscapes — like bringing more color to the design or planting perennials in a grassland-inspired design closer together to make them more noticeable. Designed plant communities can and should have margins of hedges, walkways, fences, even formal parterres to define them.
It’s a practical fusion of designs, West said, appealing to humans and recognizing that urban and suburban gardens are a far cry from the ecosystems of the past.
“It’s important to understand that a plant community is a human creation,” said author West, a landscape architect and principal at Phyto Studio in Arlington, Virginia. “In nature what we see are snapshots in time. Nothing is ever set in stone.”
What is set in stone for West is planting in layers, the guiding principle of their designed plant communities. The interlocking layers, she said, are both horizontal and vertical, with vertical playing the most important role.
Three layers of herbaceous plants were thoughtfully grouped together.
Photo by Claudia West
“It’s highly complex,” she said. “We say communities have two layers, a bottom of functional plants at the base to act as a living mulch and hold soil in place, help the flow of water into the ground, smother the weeds. On top of them is the design layer. The icing on
the cake.”
They start with the structural layer: the trees, shrubs and heavily blooming perennials planted in waves of color. The next step is to add plants to fill in the gaps as green mulch — no soil showing, please — like sedges, violets and creeping strawberry. This approach defies the traditional ways of designing in bubbles with a group of black-eyed Susans here and a group of asters there in solitary confinement with mulch as their prison bars.
“Imagine taking a bubble of black-eyed Susan and moving it into a plant community,” West said. “They may still be arranged, but not in a monoculture. They will be surrounded by other plants that grow right on top of them, all working together.”
West is quick to explain that the designed plant community is a method, not a style. As long as they’re planted in appropriate combinations in the appropriate way, the plantings can be designed as you like with no inputs of mulch and fertilizer and little or no water. This means using fewer resources, as well as less time and energy.
Signs advise gardeners to group plants with similar characteristics. Photo by Paul Bonine
Like-minded plants
Though not specifically using West’s and Rainer’s particular approach, designers and nurseries in the Pacific Northwest have long encouraged customers and clients to embrace the low-maintenance of arranging like-minded plants in the site situations they require. Paul Bonine, co-owner of Xera Plants wholesale and retail nursery in Portland, Oregon, put together signs that describe climate biomes. Around the signs, he’s arranged plants that grow in those conditions.
The biomes — xeric for summer-dry climates and mesic for summer-wet — help gardeners group plants appropriately. If they’ve got a south-facing site with reflected heat from a sidewalk, street or driveway, it’s an opportunity for a xeric landscape with cistus, ceanothus, manzanita, lavender, rosemary, callistemon, escallonia and grevillea. For mesic landscapes, he might recommend hydrangea, hosta, willow, stewartia and primula.
Customers eat it up. “It’s incredibly popular,” Bonine said. “People, especially under 30, come in saying, ‘I don’t want to water. I don’t want to weed.’ We take them to the signs. It gets their attention and they learn.”
Their branding is a matter of “edit, exaggerate, endorse.” Xera owners Bonine and Greg Shepherd choose the climate-appropriate plants they want to sell and then put those plants together in groupings in order to exaggerate and endorse them.
“Go into the Gap and there are no muumuus,” Bonine said. “They’ve edited it down to their palette and direct your attention to what they have and that’s what they sell. We do the same thing.”
Sean Hogan, owner of Cistus Design Nursery, achieves something similar by organizing plants that grow in similar conditions in the wild on separate tables. “We divided the nursery that way to give people an idea of appropriate pairings,” he said. “When I see a conifer garden with hostas, it drives me crazy.”
That said, Hogan says he’s not a “truist.” He’s happy when people learn — through observation or by talking to experienced nursery personnel or designers — to create proper plantings. Like Bonine, he wants to see native chaparral plants like live oaks, ceanothus, manzanita and madrones growing next to Mediterranean cistus, olives and rosemary, even if they aren’t native.
“It’s about being informed by the natural environment around us, but in a garden situation there’s no place we touch that we’re recreating nature. In an urban context, we’re creating pleasure and art and we’re lucky,” he said.
Amy Whitworth designed Kristen Ohlson’s front entrance with plant relationships in mind. Photo by Amy Whitworth
Up from the underground
After designing Kristen Ohlson’s garden and reading her book “The Soil Will Save Us,” designer Amy Whitworth, owner of Plan-It Earth in Portland, Oregon, became fascinated with what goes on underground.
Much of it is still not understood, but the relationship between plants and the bacteria and fungi they share through their roots is now accepted knowledge because of work by soil scientists like Elaine Ingham, a leader in research of the soil food web.
Whitworth looks to the soil and to nature for guidance when she designs a garden. She looks for plants that fit the site — soil, sun exposure, and moisture — rather than changing the site for the plant.
“What I’m looking for is low-maintenance combinations,” Whitworth said. “How to put plants together so they support each other with minimal inputs from us. They are thriving and self-supporting without our help.”
Three layers of herbaceous plants were thoughtfully grouped together.
Photo by Claudia West
The plantings at the Elisabeth C. Miller Botanical Garden in Seattle, Washington are very naturalistic but they are completely contrived, curator Richie Steffen said. He points to the woodland garden, which is a combination of native and exotic plants, all of which take the same shady, moist conditions. One bed prospers with a tapestry of black mondo grass, Anemone nemorosa, native elk fern and Cyclamen hederifolium mingled in.
Like West and Rainer, he interprets the ecological needs of the plant communities, but not necessarily the aesthetics. The reality, Steffen said, is that the design can look like anything. Still, he does have parameters: plants must need the same conditions, repetition (which doesn’t have to be drifts) and plant randomly — something almost impossible for us to do.
“We are programmed as people not to plant randomly,” he said. “It’s shocking how much practice it takes to be random, but in doing plant communities it makes it look less contrived.”
West sees, indeed strongly believes, that designed plant communities are the way of the future. “The building blocks of this new nature are resilient and native plants — and, yes, even exotic species — that are naturally adapted to environments similar to our man-made landscapes,” she said. “The question is not what grew there in the past but what will grow there in the future.”
Kym Pokorny is a garden writer with more than 20 years of experience writing for The Oregonian and other publications. She is currently a communications specialist with Oregon State University Extension Service. Kym can be reached at kym.pokorny@oregonstate.edu.
