I'm assuming this Campsis is C. radicans, as that's the American Trumpet Vine, from the Southeastern US, and this is growing in the Carolinian garden (I'm sure the sign is in there somewhere). It's very showy, and it's creeping all over the place, so the whole garden will be ablaze with it next year. This pretty low-growing aster-family thing is in the Asian garden, at (or near) Farrer Loop and Lower Asian Way. I couldn't find the sign on it either. Flowers are maybe 6cm across. I didn't get good photos of the Carpinus fangiana that's the featured tree this week. But it's the one on the cover of The Jade Garden: New and Notable Plants from Asia, by Peter Wharton, Brent Hine, and Douglas Justice (Timber Press, 2005).
Thanks, Ron. Here's a blog article on that species with a good close-up photo. I liked their description that begins This one is in the Asian garden, so it's from the right place. Thanks for the pics, Silver surfer.