Vinca, or Periwinkle, are highly regarded, low-growing ground cover plants for sun or shade producing beautiful solitary violet, purple-blue or white flowers all summer long. They have a prostrate growth habit with lance-shaped, dark green leaves, making them well suited for under-planting below trees to cover ground that may otherwise lie bare. They are highly effective for tricky situations on banks and slopes given their ability to root from leaf nodes and their trailing habit can also be used to great effect in container planting displays. Many garden designers consider them indispensable for erosion control and weed suppression and they can even be trained vertically against a wall or fence with the right support. All varieties are fairly fast growing with Vinca major being more vigorous (compared to Vinca minor) and therefore best suited to larger areas that need to be covered quite quickly. Avoid planting Vinca major in smaller areas where it may impede other plants nearby. Cut back any unwanted shoots in spring to prevent it from becoming invasive. Periwinkle should not be confused with annual periwinkle (Catharanthus roseus), which is a different plant.