Periwinkle (Vinca or Myrtle)
Periwinkles are lovely creeping vines. They wander along the ground, attaching themselves to it periodically by means of rootlets that develop along their stems at leaf joints. Also known myrtle or vinca, they are sturdy, versatile groundcovers for shady areas in home landscapes. Because periwinkle seems to thrive on neglect and tolerate urban pollution, they are ideal for city gardens. Big periwinkle (Vinca major) is popular in southern gardens, but the hardier common periwinkle (Vinca minor) is more suited for northern regions.
Size: Periwinkle trails along the ground, the stems of the large form rising 6 to 10 inches above the soil, those of the common form rising 4 to 6 inches or so (somewhat taller in dense shade). Hanging from walls or containers, their extension is limited to 1 1/2 to 2 feet. On the ground periwinkle spreads as far as it is permitted.
Foliage: Common periwinkle leaves are shiny, dark green elongated ovals slightly tapering at the ends. They have smooth edges. About 1/2 to 1-1/2 inches long and 1/2 to 3/4 inch wide, they grow opposite each other along the stems. They have a lighter mid-vein. The leaves of large periwinkle are large and rounded. They may be up to 3 inches long. Some types have variegated leaves of pale green with yellow edges.
Flowers: In early spring, pretty lilac-blue, 5-petalled flowers dot the foliage of periwinkles. About 3/4 to an inch across on common periwinkle, they are well over an inch wide on large periwinkle. Typically the flowers bloom for up to 2 months. Some varieties have deep purple, reddish-purple or white flowers.
Better Varieties: Common periwinkle: `Alba' and `Miss Jekyll's White' are white-flowered varieties. `Atropurpurea' shows reddish violet flowers and `Bowles Variety' produces prolific blue flowers but spreads more slowly. `Sterling Silver' has lavender flowers set off by dark green leaves with white edges.
Large periwinkle: `Variegata' has pale green foliage with cream-colored edges.