Vinca

Taxobox
name = "Vinca"


image_width = 240px
image_caption = Giant steps periwinkle ("Vinca major")
regnum = Plantae
divisio = Magnoliophyta
classis = Magnoliopsida
ordo = Gentianales
familia = Apocynaceae
genus = "Vinca"
genus_authority = L.
subdivision_ranks = Species
subdivision = "Vinca difformis"
"Vinca herbacea"
"Vinca major"
"Vinca minor"

"Vinca" (from Latin "vincire": "to bind, fetter") or Periwinkle is a genus of five species in the family Apocynaceae, native to Europe, northwest Africa and southwest Asia. The common name periwinkle is shared with the related genus "Catharanthus".

They are subshrubs or herbaceous, and have slender trailing stems 1-2 m (3-6 feet) long but not growing more than 20-70 cm (8-30 inches) above ground; the stems frequently take root where they touch the ground, enabling the plant to spread widely. The leaves are opposite, simple broad lanceolate to ovate, 1-9 cm (0.25-3.5 inches) long and 0.5-6 cm (0.25-2.25 inches) broad; they are evergreen in four species, but deciduous in the herbaceous "V. herbacea", which dies back to the root system in winter. Vinca will spread extremely fast.

The flowers, produced through most of the year, are salverform (like those of "Phlox"), simple, 2.5-7 cm (1-3 inches) broad, with five usually violet (occasionally white) petals joined together at the base to form a tube. The fruit consists of a group of divergent follicles; a dry fruit which is dehiscent along one rupture site in order to release seeds.

Vinca Major (also known as big leaf periwinkle) is an ideal ground cover for mountain areas of moderate climate, such as in southern California (20 deg F to 90 deg F). It is fire retardant and relatively drought resistant. It will grow thick enough to mitigate erosion on hillsides and is invasive enough to choke out undesirable grass/brush, but not too invasive to control. It grows very well in shaded to semi-shaded areas without irrigation, and will grow fine in direct sunlight if watered occasionally (though may wilt in temperatures above 85 deg F). It goes dormant in the winter and will "lay down" after a freeze, but will not die even when covered with snow for an extended period. It will return up to 18 in. tall by the beginning of summer, then slow down as the temperatures increase. With the exception of boundary control where necessary and light watering when desired, Vinca Major requires absolutely no maintenance, and will thrive even at elevations over 6000 ft.

References

* [http://www.eherbal.org/data/vinca.html Vinca medicinal uses, precautions, doses, and details]
* [http://rbg-web2.rbge.org.uk/cgi-bin/nph-readbtree.pl/feout?FAMILY_XREF=&GENUS_XREF=Vinca&TAXON_NAME_XREF=&RANK= Flora Europaea: "Vinca"]
* [http://www.virtualflowers.com.au/annuals_vinca.asp Virtual Flowers Vinca]
*Blamey, M., & Grey-Wilson, C. (1989). "Flora of Britain and Northern Europe". Hodder & Stoughton.
*Huxley, A., ed. (1992). "New RHS Dictionary of Gardening" 4: 664-665. Macmillan.