Clematis — Clematis (from Ancient Greek klematis, a climbing plant, probably periwinkle) is a genus of mostly vigorous climbing lianas, with attractive flowers. Some species are shrubby, and some others are herbaceous perennial plants. They are found throughout the temperate regions of both hemispheres, and also in mountains in the tropics. The cool temperate species are deciduous, but many of the warmer climate species are evergreen.
Most species are known as Clematis in English, while some are also known as traveller’s joy, leather flower, vase vine and virgin’s bower, the last three being names used for North American species.
One recent classification recognised 297 species of clematis. Unsurprisingly, therefore, modern taxonomists subdivide the genus. Magnus Johnson divided Clematis into 19 sections, several with subsections; Christopher Grey-Wilson divided the genus into 9 subgenera, several with sections and subsections within them . Several of the subdivisions are fairly consistent between different classifications, for example all Grey-Wilson’s subgenera are used as sections by Johnson.
Although the genus Clematis is extremely diverse many of the most popular forms grown in gardens are cultivars belonging to the Viticella section of the subgenus Flammula as defined by Grey-Wilson. These larger flowered cultivars are often used within garden designs to climb archways, pergolas, wall-mounted trellis or to grow through companion plants. Raymond Evison chronicles the history and development of these forms which normally have large 12-15cm diameter upward facing flowers and believes they largely involve crosses of c. patens, c. lanuginosa and c. viticella.