This lovely, small-flowered clematis has been listed as belonging to a number of species or crosses: C. heracleifolia, C. heracleifola var. davidiana, C. x jouiniana, and C. tubulosa. The mystery surrounding its parentage arose because it’s a spontaneous hybrid – created by bumblebees, not horticulturists. It first appeared in the garden of Mrs. Elizabeth Prentiss of Cleveland, Ohio sometime in the 1930s, and was named after the wife of her gardener, Robert Brydon. It’s now thought that C. tubulosa from China is indeed one of the parents but that the other parent is our native Virgin’s Bower, C. virginiana. Whatever its parentage, the clouds of pale blue flowers are quite ornamental. The plant form is somewhere between the shrubby C. tubulosa and the scandent C. virginiana – it leans and clambers rather than climbs.