Thumbergia grandiflora Blue Sky vine. The soft holly shaped leaves are deeply veined with large 2 inch blossom soft blue. Growing to 15 feet, it is certainly going to be the speciman plant of the garden. Hardy in zones 8a-11, and is root hardy to 20 degrees, but will freeze back at 25 degrees. Requirements are sun to part shade and do not like to have its roots standing in water