Big periwinkle (Vinca major) is a perennial ground cover native to Europe and Africa. It has shiny, thick leaves and lavender flowers. First introduced to California for ornamental and medicinal purposes, big periwinkle has escaped garden landscaping and is now invasive in coastal counties, the foothills, the central valley, and some desert counties. Big periwinkle spreads rapidly, especially in riparian areas, creeks, and drainages. Once it is established, big periwinkle forms a thick ground cover, choking out native plants and changing the ecology of the area. Particularly bad infestations can alter local hydrology.
Big periwinkle is difficult to control because it spreads aggressively through vegetative reproduction, and can resprout from stem fragments that can be carried to new locations by water. It is not deeply rooted, so small infestations can be treated manually, as long as every stem and root fragment is removed from the soil. For larger infestations, big periwinkle must be controlled with herbicide. The first priority in managing big periwinkle is to prevent it from spreading further. When choosing a ground cover for your garden, please don’t plant big periwinkle. One example of a non-invasive alternative to big periwinkle is discussed below.
Native Alternative: Douglas Iris (Iris douglasiana)
Douglas iris is a one- to two-foot tall perennial that flowers from April to June. Douglas iris produces pleasing flowers that are light blue-violet to dark purple. It grows quickly in coastal areas where there is some summer water available, and prefers richer soils with some organic matter.
Another alternative, Alumroot, is described on our English Ivy Don’t Plant Me! Page.