Avoid Growing This Stunning Flowering Plant That's Secretly A Garden Nightmare

Ground covers are great for quelling erosion or as a substitute for turf. They suppress weeds, reduce rainwater runoff, and attract pollinators. The right ground cover can shave hours off your summertime landscaping chores, but the wrong one can become a garden nightmare. A sea of stunning blue flowers rippling across the yard or marching up a hill seems like a great solution to your garden problems, but you will probably come to regret choosing periwinkle (Vinca spp.) as a ground cover. Both big leaf periwinkle (Vinca major) and lesser periwinkle (Vinca minor) are non-native, invasive ground covers that spread aggressively. If you've chosen periwinkle for its blue blooms, there are other lovely blue flowers that make a great groundcover and don't grow as aggressively.

Vinca major grows 3 to 8 inches high and up to 2 feet wide in USDA Hardiness zones 7 to 9. Its flowers are larger than those of vinca minor, a vine hardy in zones 4 to 9 that grows 3 to 6 inches high and up to 18 inches wide. The herbaceous perennials spread quickly and root wherever they touch the soil. Because of its potential to damage local ecosystems, vinca major has been reported as invasive in California, Oregon, Indiana, Pennsylvania, Virginia, South Carolina, Georgia, and Alabama, while vinca minor is invasive in Oregon, Wisconsin, New Hampshire, Indiana, Pennsylvania, Kentucky, West Virginia, Virginia, Maryland, Tennessee, South Carolina, Georgia, and Alabama as well as individual counties across the U.S.

Both vinca major and vinca minor root at the nodes, spreading quickly and vigorously. Once the plant has escaped to a natural area it will smother local species. In extreme cases and in some landscapes like riverbeds, the actual geography of the location and native plant structure can be changed. Vinca will escape your yard unless it is completely contained by barriers like concrete sidewalks. It will also happily cross the property line, making it hard to stop the invasive weed from next door. Both cold weather and full sun can limit vinca's spread, but neither will eradicate it. Hand pulling the vines is the most effective way to get rid of the plant without using herbicides as long as you get all of the stems and nodes and dispose of the weeds responsibly,. Herbicides are available that will kill vinca, but it may take a few treatments to eradicate the plant.

Instead of vinca, consider Madagascar periwinkle (Catharanthus roseus), which  has pretty blooms that are very similar to vinca without the headache of its spread. Low-maintenance and non-invasive, the perennial bedding plant is hardy in USDA Hardiness zones 10 and 11 and has 1- to 3-inch flowers in a multitude of colors, including lavender, white, pink, and gold. If you've chosen periwinkle because blue is a beautiful color to have in the garden, there are other species that don't grow as aggressively but are also stunning. Blue star creeper (Isotoma fluviatilis), hardy in zones 6 to 8, blooms in the spring and summer. This low-maintenance herbaceous perennial is easily contained with edging material.