Just throwing this out there so experts can agree/disagree.
Wonder if any sages would do well? They certainly don't mind heat. And they do ok for me in Zone 8a. But it's flatland here and I don't know if the elevation would be a factor? There is a forum called Salvias and Agastaches (or something like that). You might ask about sages there.
Does your county have a Master Gardeners group? Are there any small local nurseries? (not HD or other big box stores)
Have you already answered these 2 questions? I didn't go back to read what you said. (my bad)
