"Holy cow! I think it's a monarch," Barbara Downs says as an orange-and-black butterfly flicks across her mature Georgetown garden. "We have lots of swallowtails, but I think it's a monarch."
The excitement of this experienced gardener is clear. Little by little, for nine years, she has been adding native plants to be ecologically responsible and to attract birds and butterflies that have lost much of their habitat through pesticides.
Downs, 74, whose garden has been featured on several Georgetown Garden Tours, is not alone in her effort to plant more natives. "People used to say, 'What's a native?' " says Kirsten Johnson, president of the Maryland Native Plant Society. Founded in 1992, its membership has increased dramatically since then as plant nuts -- everyone from backyard gardeners to nursery owners -- have championed plants native to their regions.
"We used to be happy if eight people showed up for our field trips," Johnson says. "In the last five years, we've had to limit the numbers on our 50 trips. They often fill up within 24 hours." Now, she says, most gardeners not only know what a native is, but they also know that deer, development and invasive species (such as kudzu and porcelain berry) are the three major threats to them.
Downs, an artist and community volunteer, is a case in point. In 1988, when she moved from one Georgetown house to her current 1905 Georgetown townhouse, she asked a former neighbor and landscape architect, the late Jim van Sweden, to design her front and back gardens. "I was impressed that his gardens needed no pesticides," she says. His Washington-based firm, Oehme, van Sweden & Associates, pioneered the forward-thinking New American Garden style, which champions four seasons of garden interest. The firm eschews lawns in favor of swathes of perennials and grasses. When Downs' gardens were installed in 1992, the New American Garden look was at the cutting edge of design.
Originally, the gardens were filled with sun and included several natives, including leatherleaf viburnum, bottlebrush grass and oakleaf hydrangea bushes. "I look forward to that hydrangea's dark red leaves each autumn," she says. The beds in front remain sunny, and Downs has replaced a Chinese witch hazel with a native witch hazel that shows persimmon-edged leaves before they drop. To this mature, streetside area, she has added the deciduous shrub summersweet: fragrant in bloom, attractive to butterflies and golden in its fall foliage.
In the long, 1,600-square-foot garden behind her den, two neighboring trees -- a mulberry and a native river birch -- gradually turned the area shady. Downs used the changing condition to introduce native plants and trees. "They make everything so much more interesting," she says. With them, she has gained a new plant palette, and those plants have added texture to her layered and painterly garden.
"It's all about texture. I like a relaxed look," she says, standing in the middle of a garden so densely planted that no mulch is needed, only an occasional dressing of organic soil conditioner to keep the earth from becoming compacted. "Natives also bring more life," she adds.
"Native plants increase the food chain and the web of life," Johnson explains. "People love to see the butterflies (they attract), and birds feed on their caterpillars."
In Downs' garden, birds flock to the berries on the summersweet in front. Behind the house, they enjoy berries of a dogwood, the leatherleaf viburnum and an American cranberry bush. A deciduous mountain witch alder (Fothergilla) stands almost 4 feet tall, with burgundy fall foliage and fragrant spring, bottlebrush-like flowers that draw butterflies and birds alike.
For a decade, Downs has used Sheila Brady, vice president of Oehme, van Sweden & Associates, as her landscape architect. Brady was the lead designer of the Native Plant Garden at the New York Botanical Garden, which opened in 2013 with about 73,000 plants representing 454 different native species. Brady says she and Downs are passionate about including natives, "and we understand that by doing so, we simultaneously support wildlife and biodiversity. We wanted to select the right plant that fits contextually, ecologically and aesthetically."
Shade-tolerant natives now punctuate a long, curvilinear stone path, whose year-round focal points include classical sculpture and a bubbling, millstone-shaped pink-granite fountain filled on an autumn day with robins. These undulating borders include American ginger, foamflower, coral bells and various ferns, such as feathery lady fern, as well as marginal shield fern and Christmas fern, both evergreen for winter interest in this city garden.
"I'm trying to replace the Liriope with Iris cristata (dwarf crested iris) as an edging plant," Downs says, "also Carex plantaginea (seersucker sedge), both great textural plants."
Another tree event is bringing further opportunity. The neighbors' towering Southern magnolia recently came down, so sun-loving natives are a new option for Downs. Topping her list are the Virginia bluebells she admires at the nearby Volta Park, where she and her Georgetown Garden Club have been involved and which sports natives such as inkberry, bloodroot, coneflower and false indigo.
When contemplating future natives for Downs, Brady says, "As we add plants over the years, we will be careful to maintain the sense of mystery in the garden -- when you look out the window or wander along the steppingstone path, it's not clear what's beyond the fountain; boundaries are blurred."
Any addition would only further the mystery of this multilayered garden, increasingly enriched by the beneficial insects, birds and butterflies its native plants support.