Vinca Gardening | ||||
Vinca is a genus of flowering plants in the family Apocynaceae, comprising 5 species. It is native to Europe, northwest Africa and southwest Asia. Its common name is Periwinkle. Vinca is an subshrub or herbaceous plant with slender trailing stems which take root where they touch the ground, enabling the plant to spread widely and fast. The leaves are opposite, simple, broad laceolate to ovate. Vinca is evergreen in four species but decisuous in the herbaceous V. herbacea, which dies back to the root system in winter. The flowers are borne through most of the year, are salverform, simple, broad, with 5 petals of violet (occasionally white) which are joined together at the base to form a tube. The fruits are a group of follicles. Vinca is a useful groundcover as it can grow and spread quickly. Although useful and attractive, both Vinca major and Vinca minor can be considered invasive because of the rapid spreading and the possibility of choking out native species if the vines enter a forested area where it is not controlled. Vinca major (Large Periwinkle, Greater Periwinkle and Blue Periwinkle), 45 cm high, is a flowering plant native to southern Europe, northeastern Turkey and the western Caucasus. Vinca major is commonly grown in temperate gardens for its evergreen, glossy dark green foliage, blue flowers which bloom throughout spring to autumn, and vining habit. Several cultivars are available, with white to dark violet flowers and variegated foliage. The leaves of cultivar 'Variegata' (syn. 'Elegantissima') are edged with cream-yellow, and the blue flowers are produced in early summer. 'Alba' has white flowers. Vinca minor (lesser periwinkle), 20 cm high, is a flowering plant native to central and southern Europe, and Turkey. It is commonly grown as a groundcover in temperate gardens for its evergreen foliage, spring and summer flowers, and dense habit of smothers most weeds. It has few pests or diseases outside its native range and is classified as an invasive species in parts of North America. It is a trailing, viny subshrub, spreading along the ground and rooting along the stems to form large clonal colonies and occasionally scrambling up to 40 cm high but never twining or climbing. The leaves are evergreen, opposite, glossy and dark green with a leathery texture and an entire margin. The flowers are violet-purple (pale purple or white in some cultivated selections), and are produced mainly from early spring to mid summer. The fruit is a pair of follicles, containing numerous seeds. Vinca herbacea (Herbaceous Periwinkle) is a flowering plant native to eastern and southeastern Europe, southwestern Asia and Alborz ( mountain range in northern Iran) mountains. This species mainly grows in steppe habitats. It is a herbaceous perennial, growing as a trailing vine, spreading along the ground and rooting along the stems to form clonal colonies. The leaves are opposite, lanceolate, glossy green with an entire margin. The flowers are blue-violet or occasionally white, with a five-lobed corrolla, and are borne in late summer. It is occasionally grown as a rock garden plants in temperate gardens. Although Vinca is often grown as a groundcover in shade, they produce more flowers when they are in the sun. It also need moisture-retentive but well-drained soil to grow well. Propagation is by division in autumn, or semi-ripe cutting in summer. Vinca is hardy and has minimal pests and diseases. | ||||
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