- Source: Clematis potaninii
Clematis potaninii, the old man's beard, is a species of flowering plant in the family Ranunculaceae, native to Tibet and central China. A deciduous woody vine, in the wild it is found climbing on slopes and in forests, particularly forest edges, at elevations from 1,400 to 4,000 m (4,600 to 13,100 ft). Its cultivar 'Summer Snow', also known as 'Paul Farges', has gained the Royal Horticultural Society's Award of Garden Merit.