Editing Clematis (section)

==Horticultural classification==
This follows the classification adopted by V. Matthews in The International Clematis Register and Checklist 2002, except that ''C. ispahanica'', now considered to have been included in error, has been omitted from the list of parent species in Tangutica Group.<ref>[http://www.ishs.org/sci/icralist/50.htm RHS] ISHS ICRA clematis</ref><ref>[http://www.rhs.org.uk/plants/plantsmanship/plant-registration/Clematis-registration/Clematis Clematis Register] RHS</ref>
* Small-flowered Division: Flowers (1.5–)2–12(–18) cm across
** Armandii Group: Cultivars belonging to, or derived from, species classified in subsection Meyenianae (Tamura) M. Johnson, mainly ''C. armandii''.
** Atragene Group: Cultivars belonging to, or derived from, species classified in subgenus Atragene (L.) Torrey & A. Gray, such as ''C. alpina, C. chiisanensis, C. fauriei, C. koreana, C. macropetala, C. ochotensis, C. sibirica, C. turkestanica''. The former Alpina Group and Macropetala Group are included here. Historically, the Alpina Group was used for single-flowered cultivars, and double-flowered cultivars were assigned to the Macropetala Group.
** Cirrhosa Group: Cultivars belonging to, or derived mainly from, ''C. cirrhosa''.
** Flammula Group: Cultivars with at least one parent belonging to, or derived from, species classified in section Flammula DC. (excluding subsection Meyenianae (Tamura)M. Johnson), such as ''C. angustifolia, C. flammula, C. recta, C. terniflora''.
** Forsteri Group: Cultivars belonging to, or derived from, species classified in section Novae-zeelandiae M. Johnson (native to Australia and New Zealand) such as ''C. australis, C. foetida, C. forsteri, C. marata, C. marmoraria, C. paniculata, C. petriei''.
** Heracleifolia Group:Cultivars with at least one parent belonging to, or derived from, species classified in subgenus Tubulosa (Decne.) Grey-Wilson, such as ''C. heracleifolia, C. stans, C. tubulosa''.
** Integrifolia Group:Cultivars belonging to, or derived mainly from, ''C. integrifolia''. Includes the Diversifolia Group (which covered ''C.'' × ''diversifolia'' (''C. integrifolia'' × ''C. viticella'') and its cultivars).
** Montana Group: Cultivars belonging to, or derived from, species classified in section Montanae (Schneider) Grey-Wilson such as ''C. chrysocoma, C. montana, C. spooneri''.
** Tangutica Group: Cultivars with at least one parent belonging to, or derived from, species classified in section Meclatis (Spach) Baill., such as ''C. intricata, C. ladakhiana, C. orientalis, C. serratifolia, C. tangutica, C. tibetana''. This Group has also been known as the Orientalis Group.
** Texensis Group: Cultivars derived from ''C. texensis'' crossed with representatives from either of the Large-flowered Groups.
** Viorna Group: Cultivars with at least one parent belonging to, or derived from, species classified in section Viorna A. Gray, such as ''C. crispa, C. fusca, C. ianthina, C. pitcheri, C. reticulata, C. texensis, C. viorna''. Cultivars assigned to Texensis Group, and cultivars with ''C. integrifolia'' in their parentage, are excluded.
** Vitalba Group: Cultivars with at least one parent belonging to, or derived from, species classified in section Clematis L., such as ''C. ligusticifolia, C. potaninii, C. vitalba, C. virginiana''.
** Viticella Group: Cultivars with at least one parent mainly derived from ''C. viticella''. Excludes hybrids between ''C. integrifolia'' and ''C. viticella'': see Integrifolia Group.
* Large-flowered Division: Flowers (5–)10–22(–29) cm across, usually flat.
** Early Large-flowered Group: Comprises the former Patens Group and Fortunei Group. Cultivars of the Patens Group were derived mainly from ''C. patens'', either directly or indirectly. They were characterized by producing flowers in spring on the previous year's wood, and often again in summer or early autumn on the current year's growth. The former Fortunei Group (also known as Florida Group, although it had nothing to do with ''C. florida'') comprised cultivars with double or semi-double flowers that were produced on the previous year's growth in spring. Hybridization has made it impossible to keep the original Groups separate: there are a number of cultivars that produce both single and double flowers, or that only produce semi-double or double flowers under certain conditions.
** Late Large-flowered Group: Comprises the former Lanuginosa Group and Jackmanii Group. Cultivars of the Lanuginosa Group were derived mainly from ''C. lanuginosa'', either directly or indirectly. The Jackmanii Group covered cultivars produced from a cross between ''C. viticella'' (or a derivative therefrom) and a member of the Patens Group. Both Groups produce their flowers on the current year's growth in summer and autumn. It is often impossible to say whether a cultivar belongs to the Lanuginosa Group or to the Jackmanii Group, due to hybridization and/or lack of information on the parentage, so it is not possible to maintain these Groups.