Can anyone help me find a great, white clematis that can handle lots of sun and heat? I would love one that will produce lots of flowers and climb over an arch. If it has a little bit of purple on it, that would be fine too. It will be in 4-5 hours of direct sun. So many of the descriptions online show that they can handle full sun, but from what I've read on this board, I don't think most of them can handle full sun in Tx. I would love any recommendations!