ARLINGTON – Planting groundcovers to fill bare spots, shore up slopes, serve as lawn alternatives or beautify landscapes presents both ecological rewards and potential pitfalls.
Groundcovers can cool the ground, retain moisture, and reduce soil compaction and erosion, while filtering and slowing rain runoff. And an appropriate groundcover will reduce yard maintenance as a “green mulch,” said Elaine Mills, a Master Gardener in Northern Virginia.
Virginia Cooperative Extension Master Gardeners encourage Virginians to choose native groundcovers suited to local soils and climates. Not only can they add beauty and interest through the seasons, but they also double as a critical resource for wildlife.
However, non-native groundcovers designated as invasive in Virginia, including English ivy and periwinkle, are widely available to consumers. They can escape cultivation as seeds are carried by wind or animals into natural areas.
“There, they can invade the understory of forests, spreading further by rampant vegetative growth and producing a dense monoculture that suppresses native herbaceous plants,” Mills cautioned.
But native options abound at garden centers. Thriving in sun, shade or both, groundcovers can be herbaceous or woody, flowery or grassy. They may grow in clumps, mounds, carpets or mats.
“The choice of an evergreen, woody perennial or herbaceous groundcover depends on your preference and scale of the landscape,” said Alex Niemiera, a professor at the Virginia Tech School of Plant and Environmental Sciences.
Some species are ideal for edging garden paths, draping over walls or filling in hot, dry curbsides called “hell strips” where other plants can’t grow, Mills said.
And if the function of a groundcover is to minimize weed growth, “then the groundcover should be evergreen, and deep and thick enough to deter weed seedling growth,” Niemiera added.
Native perennials for sun include Phlox subulata, or moss phlox; Antennaria plantaginifolia, or plantain-leaved pussytoes; Opuntia humifusa, or eastern prickly pear cactus; Salvia lyrata or lyreleaf sage; and Symphyotrichum oblongifolium, or aromatic aster.
Shade-loving groundcovers include Podophyllum peltatum, or mayapple; Polystichum acrostichoides, or Christmas fern; Asarum, or wild ginger; Viola, or violets; and Solidago caesia, or blue-stemmed goldenrod.
Consider grasses and rushes like Schizachyrium scoparium, or little bluestem; Juncus effusus, or common rush; and Chasmanthium latifolium, or river oats.
Low-growing woody natives include Juniperus horizontalis, or creeping juniper; Rhus aromatica, or ‘Gro-Low’ fragrant sumac; Hypericum prolificum, or shrubby St. John’s wort; and Parthenocissus quinquefolia, or Virginia creeper.
Visit bit.ly/3PgDLp5 for a native groundcovers webinar. Read the full story in Virginia Farm Bureau’s spring Cultivate magazine at bit.ly/3QuKAUC.