Yellow Flowering TrumpetVine. This native species is ubiquitous throughout the Eastern U.S. where it has invaded almost every farm fence. But, this cultivar has 2 1/2" to 3" yellow trumpets at the terminus of each stem from late spring to early fall. This is a much more pleasing selection than the glaring orange flowers of the straight species. Much like Bignonia, of which it is a close relative, this vine climbs by aerial roots which will cling to any textured surface such as a wall, fence or post.