Clematis is a genus of about 380 species within the buttercup family, Ranunculaceae. Their garden hybrids and cultivars have been popular among gardeners, beginning with Clematis 'Jackmanii', a garden staple since 1862; more cultivars are being produced constantly. They are mainly of Chinese and Japanese origin.

Ranunculaceae is a family of over 2,000 known species of flowering plants in 43 genera, distributed worldwide.