Common Periwinkle is an herbaceous evergreen perennial with a ground-hugging habit of growth. Its medium texture blends into the garden, but can always be balanced by a couple of finer or coarser plants for an effective composition. This is a high maintenance plant that will require regular care and upkeep, and should not require much pruning, except when necessary, such as to remove dieback. Deer don't particularly care for this plant and will usually leave it alone in favor of tastier treats. Common Periwinkle has masses of beautiful purple flowers along the stems from mid to late spring, which are most effective when planted in groupings. Its small glossy oval leaves remain dark green in colour throughout the year. Common Periwinkle will grow to be only 4 inches tall at maturity, with a spread of 24 inches. Its foliage tends to remain low and dense right to the ground. It grows at a fast rate, and under ideal conditions can be expected to live for approximately 10 years. As an evergreen perennial, this plant will typically keep its form and foliage year-round. This plant performs well in both full sun and full shade. However, you may want to keep it away from hot, dry locations that receive direct afternoon sun or which get reflected sunlight, such as against the south side of a white wall. It prefers to grow in average to moist conditions, and shouldn't be allowed to dry out. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments, and will benefit from being planted in a relatively sheltered location. Consider covering it with a thick layer of mulch in winter to protect it in exposed locations or colder microclimates. This species is not originally from North America. It can be propagated by division. Common Periwinkle is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. Because of its spreading habit of growth, it is ideally suited for use as a 'spiller' in the 'spiller-thriller-filler' container combination; plant it near the edges where it can spill gracefully over the pot. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden.
