The ultimate local ecotype might be right outside your door, just waiting to resurface and reclaim the land
Common evening primrose is an outlier, always hanging around the edges of the garden party but banished from the inner circle. As its scientific name implies, Oenothera biennis has a two-year life cycle, lending it an air of unpredictability (“Now you see me, now you don’t!”). It seeds around, spreading the love in the most unlikely places, including in cracks in the asphalt.
Its sister flower, Oenothera fruticosa, has managed to make its way into the clique. Considered cuter and less “rangy,” it’s shorter and, in the parlance of rigid rules imposed upon garden plants, it knows its place. O. fruticosa inspires an anachronistic phrase often used in the landscaping industry that evokes the days of corsets and ladies’ umbrellas: “well-behaved.” It even has a more crowd-pleasing common name, “Sundrops,” implying a smattering of floriferous joy splashing around the garden scene like a dab of color in a Renoir. And it surely deserves the title. But so does O. biennis.
It’s been at least 20 years since I met the wilder flower for the first time, and this month marks the 10-year anniversary of the launch of the Humane Gardener website, where I paid tribute to O. biennis in one of my first posts, “Common Evening Primrose: Not So Common, Not So Prim.” The time in between has brought a growing interest in other neglected native plants whose reputations I’ve sought to elevate in my writing and presentations, including nimblewill, burnweed, late boneset, Virginia creeper, fleabanes, three-seeded mercury, violets and pokeweed (which is such a superstar I couldn’t help but honor it a second time).
O. biennis hasn’t garnered the same level of public affection yet, except among our wild friends. Animals gather readily around its stalks that appear seemingly overnight, shooting up above the viburnum, past the burnweed, and into the morning and evening light (the flowers are especially fond of dawn, dusk and cloudy days). This plant has many appreciative fans, including bumblebees, skippers and carpenter bees, who are too big to enter blooms the conventional way. Instead, they engage in a phenomenon known as “nectar robbery,” drilling into stems and bases of flowers:
Goldfinches devour the seeds and leafcutter bees excise circular pieces from leaves to line their nests. Deer and rabbits nibble on O. biennis, which also attracts sphinx moths and other nocturnal pollinators, making it a recommended species for bat gardens. So many insects hang around common evening primrose that this year, when the hummingbirds swooped in to sip nectar, they also appeared to be foraging for protein:
For all its bounty, O. biennis’s only other appearances in my community are in the lands of the forgotten. I’ve spotted a few on the shoulder of the highway that will likely be mowed before they go to seed. Past the bridge on our way to the farmer’s market in town, a patch has sprung from the ditch. Two weeks ago, one lone stalk began flowering near the train tracks, along with a couple of baby sycamores, but last weekend it was gone without a trace.
A Sense of Place Starts in the Seed Bank
O. biennis is just one of many industrious self-starters that thrive in my central Maryland habitat and tend to appear without prompting or pampering. These plants are the ultimate local ecotypes, growing from the seeds of species that not only evolved in my state, county and hometown—but even, perhaps, on this particular patch of earth. While some blow in with the winds and on animals’ feet and fur, others have likely been in the seed bank for generations, buried in layers of soil, waiting for their chance to resurface and grow up toward the light.
During a volunteer stint helping to digitize herbarium records, a peek at the hundred-year-old specimens confirmed my suspicions about what once grew naturally here. So did reading the work of a nature writer who wandered nearby woods and meadows before they were cut down and filled in for human dwellings. In her 1976 book Wildlings, among musings on woodcocks, persimmons, goldenrods and tent caterpillars, Mary Leister devoted an essay to a large patch of common evening primrose. Wandering down a path well-worn by foxes, through the milkweeds and tall grasses, she came upon the flowers just as they greeted the moon:
Now, like corn in a popper, the yellow flowers in the primrose forest and the yellow stars in the night-dark sky began popping into the world. Here. There. Right. Left. Up. Down. And all I could see was the lightness of flowers and the brightness of fireflies and stars. And, now and again, the silhouette of a dark sphinx moth hovering before a yellow blossom. Three pale-winged, pale-bodied sphinx moths (probably willow- or poplar-sphinxes) drifted from blossom to blossom and these I could see, close by, in the darkness.
Did my popping primrose friends descend from the ones Mary admired so long ago? It’s possible. A 1987 paper in the Canadian Journal of Plant Science noted that primrose seeds usually fall within a meter of the plant. Birds may also spread them, but the most likely means of dispersal, the researchers wrote, comes on the wheels of vehicles and equipment. Wherever they land, they’re tough survivors; an experiment begun in the nineteenth century found that O. biennis seeds remain viable in the soil for at least 80 years.
Traveling through Time in the Seed Bank
If conditions are right, seeds in a home habitat might abound at the surface. By the time we moved to our home in 2000, decades of mowing had eroded the top layers of the land sloping toward the woods, revealing bare areas where seedlings could take hold. Closer to human-built structures, though, seeds might be buried more deeply under fill dirt, as my husband and I discovered following a pond project. After digging two feet down and piling soil thickly atop nearby turf, we were gifted with plants we had never seen on our land before: splitbeard bluestem, deertongue grass and several other Dicanthelium species. Excavation of two smaller tub ponds yielded more bounty, including Canadian clearweed seeds that continue to spread and fill gaps in shadier areas.
The effects of our mini paleoecological dig were not unlike those Scott McGill used to see as the founder of a Maryland-based stream restoration company, Ecotone. Seeking to level out deeply incised waterways and return them to functioning wetlands, his crews removed anywhere from two to six feet of “legacy sediment,” the term for soil that has accumulated over three centuries of land-clearing for mills, agriculture, road building, lumber operations and mining.
Buried deep underground, they found a rich black layer filled with remnants of pre-colonization. “It’s only six to eight inches thick in many cases, and that represents 15,000 years of deposition,” McGill told me. “You’ll even find wood. It’s almost sort of a Mt. Vesuvius kind of effect, where everything was sort of buried in ash and preserved. All that sediment deposited on this peat layer so quickly, relatively speaking, that that seed layer has just been sitting there waiting for this sunlight or something that triggers it to germinate.”
After Ecotone’s crew spread the peat along the surface of regraded areas, they watched viable seeds of dozens of species sprout, including some that have also volunteered all over our land: false nettle, beggarticks, jewelweed, boneset and especially sedges and rushes—seeds of the past that we nurture in the present, hoping they will feed and shelter wildlife for generations to come.
A Wildly Different Approach to Restoration
Just as I was finishing this article this week, the Washington Post published a beautiful piece featuring scientists in California who believe that seeds lying dormant in the soil are one of our best safeguards against an uncertain future. At McLaughlin Natural Reserve, the Post team came upon research director Cathy Koehler crawling around the meadow, pulling invasive grasses by hand:
Whereas traditional restoration projects often involve sowing seeds in an attempt to revive dwindling species, Koehler sought to remove competitors and make space for plants in the seed bank to reemerge.
She hoped this tactic would yield a more resilient ecosystem. In contrast to commercially produced seeds, which come from carefully tended plants grown in nurseries, organisms in the seed bank are keenly attuned to the specific stresses of their environment. “Restoration that approaches it from the use of a seed bank that still exists—to me, that is more powerful,” Koehler said.
Cultivating this kind of respect and appreciation for the land has been central to my writing and presentations over the years, and I don’t think it needs to be limited to nature sanctuaries or other large properties. Increasingly, I’m heartened by how many other people are honoring long-neglected plant friends in their habitats, celebrating each pokeweed sprout and three-seeded mercury that finally feels at home again. But online groups and other resources dedicated to the topic have made it clear that I still have my work cut out for me. Despite exploding interest in native plants, social media conversations are still filled with warnings about native species that spread “too aggressively” or lack people-pleasing star quality. Landscaping books and websites are rife with advice to firebomb entire spaces with herbicides before starting a native plant garden anew.
Decades of living in a dynamic space has led me to a wildly different (or differently wild?) approach. By giving plants space and time to grow and evolve with the seasons, I’ve learned that even the most vigorous natives reach their natural limits once they become part of a broader, more diverse community. And by resisting herbicides in favor of gentler cultivation methods, I’ve been able to protect a secret stash of countless seeds and seedlings—and together we welcome many of their animal collaborators back home.
The Benefits of Hardy Volunteers
Focusing at least some of our habitat restoration efforts on nurturing the self-starters can glean some important but less-considered rewards:
Local fauna have evolved with local flora: As I wrote in my book Wildscape, individuals or populations of the same plant species can have different chemical compositions and therefore different effects on insects who visit them. When we nurture plants of local origin, we may have more guarantees that wildlife will thrive among them.
The plants are already well-adapted. They’ve evolved in local soils and weather conditions, so there’s usually less need to help them along. Also, they chose where to sprout; it’s their homeland, after all.
Native plants sprouting from the seedbank don’t carry the same risks. Every time we import plants into our habitats, we risk introducing new pathogens and organisms that may not have evolved in our region.
You aren’t feeding irresistible “potato chips” to herbivores. Grown to look appealing for sale, nursery plants are usually fertilized and sometimes unnaturally lush. That can make them more susceptible to mammal nibbling.
Resilient plants tend to spread and feed more wildlife. If a plant likes the spot it chose for itself, it’s likely to reproduce. As long as your goal is diverse and abundant habitat, this should come as great news. The more you have growing, the more you can share with wild neighbors.
Six Steps for Nurturing Local Seeds
A habitat in transition occupies an aesthetic space well outside cultural norms, so the slow-gardening approach may at first look haphazard to human eyes. But following nature’s lead is an intentional act, demanding little more than our attention, creativity and care. Here are six steps for getting started.
1. Create refuges from the cutting blades.
To discover what might be capable of growing, stop mowing for a while, even if you do it one patch at a time. Yards of all sizes can harbor treasures in the turfgrass just waiting to be released; you only have to look at hellstrips, tree pits, and other in-between spaces to see this in action. (If you’re in a community with strict rules, find a hidden spot under a tree, near a fenceline, or in a similar out-of-the way place.)
Once you see a native you’d like to nurture, you can carefully dig out surrounding turf and other introduced species to give your treasure some breathing room. When deep roots make that too difficult, cut and smother the plants with newspaper topped by organic matter. Depending on the dynamics of the space, you might need to employ a combination of methods for best results.
Digging up or smothering new strips of lawn each season will help welcome more spreaders and reseeders. Suppressing turf with piles of leaves or woodchips also invites volunteers. When an invasive Bradford pear succumbed to Tropical Storm Isabel in 2004, we covered the area with cardboard and woodchips made from the fallen tree, and within a few years it sprouted into a native woodland of walnuts, sassafras, spicebush, hickories, and black locusts. Sedges, snakeroot, white avens, enchanter’s nightshade, ferns, blue mistflower and golden ragwort cover the ground layer—but only the last one was planted by me.
2. Give plants the benefit of the doubt: don’t assume “weediness.”
If you’re unsure of a plant’s identity, identification apps like iNaturalist can often help you learn the name of your new green friend within seconds. Even when a match is not assured, you’ll at least have a starting point for further research. (See Resources below). Become accustomed to viewing plants as living beings that form their own intricate communities, rather than objects existing only by the grace of your own designs. This will open your mind to more possibilities. Just this week, I discovered a new-to-me grass that looked surprisingly at home here in our habitat, only to realize that it likely is at home—in its historic range, among some of its favorite companions.
A quick search confirmed my hunch. Paspalum setaceum, also called hairy beadgrass, thin paspalum, or slender beadgrass, is native to much of the U.S., Ontario, Mexico, Central America, and the Caribbean. It’s a host plant for the southern broken-dash and the clouded skipper, and it feeds rabbits, deer, geese, doves, turkeys and other birds. Predictably, because it grows where it wants to, many lawn companies and extension services characterize it as a turf invader in need of spraying, mowing, or otherwise destroying.
3. Cultivate connections: encourage communities.
Plants know where they want to grow. Invite them to settle into their chosen homes, even if that means burnweeds popping up among woodland sunflowers and purpletop grasses moving into the mulch around chokeberries. Encourage these travelers to create their own neighborhoods, and you’ll watch new relationships unfold. You’ll see native grasses and chemically fortified wildflowers forming protective shields around plants more vulnerable to browsing. You’ll notice shady characters—the native groundcovers that thrive under trees—taking refuge in burgeoning woodlands. In our own yard, an area around our patio was mostly turf until a lone sassafras tree volunteered. I call it the tree that launched a habitat, suckering its way through the soil above the retaining wall and eventually inviting walnuts, hackberries, pokeweed, black cherries, black raspberries, and more new friends each year.
By nurturing these connections, you can help the land yield new surprises as it learns how to grow and live largely on its own, with only a little help and appreciation from you.
4. Nurture the pathfinders: don’t just remove; relocate!
As they break down, paths of pine needles, woodchips or mulch are great seeding grounds for native plants. Many species also sprout in crevices between stones and cracks in asphalt and concrete—purple lovegrass, aromatic aster, shrubby St. John’s wort, to name a few. When they’re small enough, it’s easy to pluck these seedlings out after a rain and move them elsewhere, no shovels required.
When several natives grow together in a spot where it’s not practical to leave them, sometimes I scoop out the entire assemblage and transplant them together, a little self-starting village of seedlings that will eventually find new ground wherever they see fit.
5. Celebrate the shy wallflowers: encourage volunteer “filler” plants.
Click to view slideshow.
The conventional landscaping world’s fixation on monocultures of invasive groundcovers, from vinca to English ivy, has had an outsized influence. Many eco-minded gardeners understandably want to add native species that help hold the ground from encroachment, and I’m certainly a huge proponent of this concept. But monocultures don’t make for the best habitats, and we can’t expect any single native species to fulfill the ground-covering role all by itself, holding space in perpetuity. As conditions change and faunal communities respond accordingly, plant communities shift too. Anyone familiar with the seemingly unstoppable Packeras will be surprised to learn, for example, that a dense patch of them mysteriously vanished this summer from one of our redbud understories, even though they’re thriving elsewhere. Fortunately, sedges, rushes, clearweed, and violets have been waiting in the wings, eager to take over the job.
Even more filler plants—such as cinnamon willow herb, nodding spurge, rabbit tobacco, and some of the diminutive Dicanthelium grasses—volunteer in the sunny meadow areas. I think of them as shy wallflowers among the more colorful or taller wildflowers, less conspicuous to us humans but attractive to small bees, butterflies and birds. Working together, they can weave into a dense matrix.
6. Find splendor in the stiltgrass: remove nonnatives carefully.
Though we tend to think of many introduced species as smothering everything in their paths, these fast-spreading plants sometimes nurse along hidden natives like panicledleaf ticktrefoil (Desmodium paniculatum) and provide temporary shelter for wildlife in disturbed environments. Pulling stiltgrass, an annual that crowds out woodland habitat, often reveals lush patches of native nimblewill where pickerel frogs, toadlets, and spiders spend their days.
In our habitat, beaked panicgrass, wrinkleleaf goldenrod, false nettle and blue mistflower volunteer among the stiltgrass and compete successfully for space, and each year I help them along by pulling more stiltgrass around them. Wineberry and multiflora rose nurse along baby oaks and other native tree seedlings. And before we cleared it, an old, thickly rooted mugwort patch circled the wagons around walnuts and black raspberries that sprouted in their mist; both would have been nibbled prematurely without that tall, scented, herb to hide them at the most tender stage of their lives.
Of course, it’s even better when the work of protecting more vulnerable young species falls to native grasses, brambles, and stalwart wildflowers. But the more you adopt a slow-gardening approach, the more they’ll show up too, bringing with them the animals who will eat, dig up, and spread more seeds across the landscape, gracing your habitat with the most local of local ecotypes you could possibly hope to find.
All photos and videos: Nancy Lawson/HumaneGardener.com
Related Articles:
For other pieces about nurturing the wilds in your home habitat, check out Give Weeds (and Animals) a Chance, #WeedsNotWeeds, Is Your Yard Undergrown?, How to Fight Plants with Plants, and The Plants Are Coming Home (my guest blog on IzelPlants.com).
Also see pieces about favorite species, including nimblewill (The Best Native Grass You’ve Never Heard Of), burnweed (Life in the Burnweed), late boneset (Boneset: You Have a Branding Problem), violets (How to Save the Violets—and Why They Matter) and pokeweed (Pokeweed, Please Forgive Me and Pokeweed: Something to Write Home About), white avens/enchanter’s nightshade/snakeroot (Dracula’s Garden: 3 Great Groundcovers), broomsedge (Spendor in the Grass) and of course my first one about common evening primrose (Common Evening Primrose: Not So Common, Not so Prim).
Resources
The iNaturalist app is the quickest, most reliable way to identify plants. Online accounts and discussion groups, including Facebook pages of state native plant societies, can be helpful too, as long as you’re discerning (crowd-sourcing is not always reliable). To learn more about a plant I’ve seen for the first time, I pull out my field guides, comb the Internet for research papers, and visit these sources: Illinois Wildflowers, Ladybird Johnson Wildflower Center, Native Plant Trust’s Go Botany, and Maryland Biodiversity Project (which recently integrated its data with iNaturalist). The species reviews on the USDA’s Fire Effects Information System include helpful tidbits about floral and faunal communities. Bplant.org is a newer site created by a kindred spirit who likes to go down the same rabbit holes that I do and has created systematic, deep-dive plant profiles. But to truly get to know a plant, nurture it, celebrate it, check on it throughout the seasons, and get down on your belly and watch it grow!