saxifrages in 6b?

Will saxifrages survive a summer in the Philadelphia suburbs? Are there species or cultivars that are more heat tolerant than others? Thanks!

Hi,
I can't answer your question directly, having no gardening experience in your area. I would, however, suggest you take a look at the following link, which may be helpful:
http://nargs.org/smf/index.php?topic=799.msg11835#msg11835

Thanks altagardener!