A rambling rock walkway leads into a little piece of magic at this ARMN-maintained demonstration garden at Potomac Overlook Regional Park in North Arlington.
Come to see shade-loving ferns and sun-basking Butterfly Weed. Observe the changing seasons through locally native plants that support essential pollinators and other wildlife. And imagine what those plants might look like in a garden of your own.
The demonstration garden may be at its finest in the spring, with a burst of Golden Ragwort and Redbud blooms followed by numerous spring ephemerals (plants that complete their life cycle in spring and then disappear). Virginia Bluebells, trilliums, phlox, Green and Gold, Dutchman’s Breeches, Common Wild Ginger, Foamflower, Early Meadow Rue, and a whole range of sedges burst into bloom in April and May.
Summer brings ferns and penstemons, Beebalm, milkweeds, mountain mints, Black Cohosh, and Joe Pye, transitioning to asters, goldenrods, switchgrass, and eupatoriums into fall. There are native shrubs, too (many are in wire cages to protect against deer): Wax Myrtle, Sweetbay Magnolia, Shadbush or Juneberry, Witch Hazel, viburnums, and Silky Dogwood.
You can find a full plant list and more information about each species featured in the Potomac Overlook garden here.
Designed for shade, but nature had other plans
The demonstration garden was created in 2011 with grant monies administered by the Audubon Society of Northern Virginia to complement the launch of their Audubon at Home program. Naturalist Cliff Fairweather approached the Arlington Regional Master Naturalists (ARMN) to help find a site appropriate to show all the native species that could be incorporated into the shady backyards that are common in the region.
The space chosen at Potomac Overlook – once the site of a farm building whose foundations can still be discerned – was already planted with a mix of exotic and native species under a healthy mixed canopy that includes a rare blooming American chestnut.
A few small trees were purchased, but the majority of plants installed were donated by Master Gardeners of Northern Virginia, Arlington Regional Master Naturalists, the Virginia Native Plant Society and Earth Sangha.
Over the ensuing years, however, a series of large trees that shaded the area died or were felled during storms.
These events radically changed the light regime in the garden, which called for an extreme remake of some of the beds from shade to sun. We were again helped by the generosity of volunteers, the Virginia Native Plant Society, and Earth Sangha.
Top challenges: Overabundant deer and invasive plants
In the parkland surrounding the garden, overabundant white-tailed deer are eating many native plant species into decline, including young oaks and groundcovers that are essential to insects, birds and other wildlife.
Only a few native plants that are unpalatable to deer, such as Spicebush and Pawpaw, are able to grow unimpeded, along with a flood of invasive exotic plants such as Bush Honeysuckle. ARMN volunteers are striving to restore balance by removing invasives and protecting native plants where we are able.
In order to prevent deer from destroying the demonstration garden plants, repellants are applied monthly and have had some value. We have also found an effective strategy to be co-planting vulnerable species with plants that are unpalatable to deer (such as plants in the mint family).
Invasive plants also seed themselves liberally in the garden and some natives are vigorous to a fault. To hold them back, ARMN volunteers meet every other week to weed and perform other maintenance during the growing season.
We are continually learning what plants are happy in the moist, rich and largely undisturbed soils in this garden, one of three native plant demonstration gardens maintained by ARMN (others are at the Arlington Central Library and Dora Kelley Nature Park in Alexandria). Like all gardens, our demonstration garden is always in transition.
To visit, park at the main shelter at Potomac Overlook Regional Park and walk down the partially gated roadway about half a mile. The garden is on the left, just after a demonstration vegetable garden. If you are interested in having a tour of this garden or in attending a work party to talk about native plants for your garden, please contact us.