Vinca is a stubborn vining plant but there is a way to outwit any groundcover that is a nuisance: grow something taller that will eventually shade it out. But in this case Vinca minor is much more than a garden nuisance; it is a known invasive species that displaces native plants in the wild. I will tell you how to get rid of it in your own yard, and you may want to share the information with your neighbor as well. Labor intensive and tedious, the following process requires diligence over several years in order to be successful.
First, find out if your neighbor will cooperate with you on the Vinca removal. If not, you may want to install an underground barrier (wood, rock or metal) between you and your neighbor's yard. Remove all the Vinca down to the root level; you can use a weed eater for this if you have a large area to cover. Place overlapping sheets of cardboard on the soil and wet well. Cover the wet cardboard with at least 6" of shredded and/or composted mulch, and wet well. Keep the area moist at all times and remove any sprouts that emerge during this next growing season. Be sure to keep the mulch thick and packed. You are in effect wearing out the plant as it tries to reach the light and just keep pulling the few runners that make it to the surface.
Meanwhile begin selecting your plants for installation in the fall. Use our zip guides to learn about native plants suitable for your state, and then visit a local native plant nursery to choose plants for the project. If you need help finding a native plant nursery in your area, visit the Lady Bird Johnson Wildflower Center website for a listing of Pennsylvania native plant and seed sources.
Be patient and in time the shrubs, grasses, ground covers and blooming perennials you install will shade out any Vinca that pops up. The resulting diverse landscape will benefit wildlife as well and you will have done your part in limiting the damage done by a highly aggressive plant. Good luck!