Thursday, July 5, 2012

Vinca Minor (small Periwinkle And Dwarf Periwinkle)


 
 Vinca minor*, Dwarf Periwinkle


Vinca minor, Lesser periwinkle and Dwarf periwinkle, is a native plant to central and southern Europe, from Portugal and France north to the Netherlands and the Baltic States, and east to the Caucasus, and also in southwestern Asia in Turkey.

It is a trailing, tiny sub-shrub, spreading along the ground and rooting along the stems to form a large colony. On occasion this plant will scramble up to 40 cm high without twinning or climbing. The leaves are evergreen, opposite each other, approximately 5 cm long and 3 cm wide, shiny dark green with a leathery texture.

The flowers are solitary and are produced mainly in the early spring to mid-summer. The fruit is a pair of follicles which contain numerous seeds.

It makes an excellent ground cover because of its dense growth, evergreen foliage, spring and summer flowers, ease of culture, and dense habit that smothers most weeds. 'This species has few pests or diseases outside its native range. In some parts of North America it is classified as an invasive species.

This species has numerous cultivars that have different flower colors,and varying color foliage such as white leaf edges (Argenteovariegata), yellow leaf edges (Aureovariegata)
Interestingly, this species has a place in the halls of medicine. Dried leaves, aerial parts, and in some cases the entire plant are used to enhance blood circulation, including that of the brain, enhance metabolism in the brain, and to treat cardiovascular disorders. It is the backbone of Vincamine, a pharmaceutical molecule responsible for Vinca's nootropic activity.

Nootropic are drugs, supplements, nutraceuticals, and functional foods that improve mental functions such as cognition, memory, intelligence, motivation, attention, and concentration.

Also, Periwinkle is considered an excellent all-round astringent that maybe used internally or externally. Its main use is in the treatment of excessive menstrual flow.. It can be used in digestive problems such as colitis or diarrhea where it will act to reduce the loss of fluid or blood while toning the membranes. It may also be used in cases of nose bleed, bleeding gums, mouth ulcers or sore throats. It has a questionable reputation for aiding in the treatment of diabetes.

Other than medical value, what is the main consideration for vinca minor? It is an evergreen perennial of the broad-leaf variety with a creeping habit, making it an ideal ground cover. Vinca minor vines stay short, sprawling out over the ground approximately 3 – 6” off the ground. They put out the bluish-lavender 'periwinkle flower' in spring and bloom intermittently throughout the summer.

To successfully establish Vinca minor as a ground cover, requires good drainage, partial sun to full shade. It would be an excellent selection for an area with dry shade, while the plant would grow more aggressively in moist soil, Vinca minor vines are reasonably drought-tolerant once established. Vinca minor vines thrive in humus rich soil but will tolerate poorer soil conditions.

A caveat about growing Vinca minor vines which are considered somewhat invasive and if this is a concern, make it a routine annual check to keep the runners in check. However, remember that the so-called invasive plant is a vigorous grower, meaning that they tend to be successful at filling in an area which is the property one wants for a ground cover.