Amanda, Welcome! You have quite good collection there.
There are no semps out there that is fully adapt to Texas Summer, however your best chances to grow sempervivums will be Tectorum and Heufelli series with some protection during summer from early June until October. You mentioned 40% shade cloth, try to use at least 70%. When temperatures above 85°. I believe Kevin is working on new sempervivums with Tectorum parentage. I will try those here North Texas once they are available.
I have been growing semps. since summer of 2017. I did not even know what Sempervivum was before then. I am growing them for winter interest. They look wonderful from early March till June. Night temperatures are very important, they grow healthier in 50°and 60°F. They are very heat tolerant with a couple exception they have to be under filtered sun after 11AM and need to be watered lightly twice a week early morning or late night.Other thing is that they have little tolerance to harmful soil pathogens so make sure soil you use well drained and use organic fungicide but fungus find the way in shady spots in humid southern regions, infecting plants during summer especially after rain. No protection need during late fall, winter and spring. Keep it up and good luck.
Ridvan
