A real winner over three years: Rudbeckia Maxima, Giant Coneflower. Brown-eyed Susan, 4' - 6' tall. Planted 3 against the fence. Happy to report that one has bloomed this year! Update 5/30/2013: My coneflowers are over 7 feet tall, and all abloom!
Virginia Creeper in Cambridge UK but native to Oklahoma
Bush's Poppy Mallow can mature to 2' in height but will often be seen spreading out rather than up. Its magenta flowers are a real stand-out in any planting. It prefers drier soil conditions, full sun to partial shade and has a long bloom time through the summer months. Callirhoe species also are called "Winecups."