Big leaf periwinkle is a dense, fast-moving ground cover that roots wherever its stems touch soil, which is precisely what makes it so effective and so problematic in equal measure. The blue-to-violet flowers open in spring and return intermittently through autumn, hovering above leaves that are broader and thinner than its smaller cousin Vinca minor. Variegated cultivars bring gold and yellow into the foliage picture, giving some ornamental justification even when the plant is not in bloom.

Classified as invasive in Virginia, South Carolina, Georgia, Alabama, and California, and flagged by the NC Invasive Plant Council, this is a plant that asks for careful placement. It can be grown in containers in zones cooler than 7, which keeps its wandering habits in check. Moving water can carry stem fragments downstream to establish new colonies. Where it is used, sites with heavy shade and steep terrain where erosion control is paramount offer the most defensible rationale for planting it.