Periwinkle Vinca major

Big leaf periwinkle is an evergreen, herbaceous perennial ground cover from southern France to Asia Minor that forms a dense mat. It is a member of the dogbane family (Apocynaceae). The species epithet means larger.

It tolerates high heat and nearly full shade but prefers partial shade, or dappled sunlight and moist, fertile soil with good drainage. It grows 3 to 8 inches high and 1 to 2 feet wide, which makes it seem like a relatively small plant, but its rapid growth rate and ability to root at the nodes enables periwinkle to form a dense mat over a wide area and become weedy and high maintenance. The blue-to-violet flowers appear in spring and may bloom intermittently through autumn. It can be grown in containers outside of zone 7.  Its non-flowering stems grow along the ground, with the flowering stems standing upright.  

This plant is considered invasive in VA, SC, GA, AL and CA. It is classified as an invasive species by the NC Invasive Plant Council. It spreads as its nodes come in contact with the surrounding soil, forming roots. Moving waters can also dislodge pieces of the stems and wash them downstream where they can form additional colonies.

The two species of periwinkle in cultivation differ as follows:

• Vinca major has leaves that are broadest below the middle, and the leaf bases are cordate (heart-shaped) to nearly rounded. The leaves are thin in texture (relative to the other species) and ciliate on their margins. The flowers are larger than other species.
• Vinca minor has leaves that are broadest near the middle and the leaf bases are rounded to cuneate (wedge-shaped). The leaves are thick in texture (relative to the other species) and not ciliate on their margins. The flowers are smaller than other species.

Quick ID

• Stems vine-like, unbranched
• Leaves opposite, ovate, ciliate
• Flowers rotate, bluish

Insects, Diseases, and Other Plant Problems:  This evergreen can spread aggressively, becoming invasive as it spreads to adjacent beds and lawns, particularly in southern locations. In locations where its aggressive growth is unchecked, it can crowd out native plants and degrade animal habitats.  Insects that may affect this plant include nematodes and aphids. Disease issues include root rot, leaf spot and blight. It is a known host to a bacterium that may cause Pierce's disease, a deadly disease for grapevines.