Texas vs Succulents

Texas (Central Texas at least) is not so nurturing of all succulents.  Here is an example of three species that can only survive in Texas given a protected environment in the shade.   Echeveria runyonii - top, Sempervivum ‘Emerald Empress’ - right, Bitter Root Lewisia rediviva- bottom.  While they may thrive in the winter time here, they die in the summer if not hidden away from the sun and watered consistently.  I would guess its not the intensity of the sun that kills them but rather the length of the exposure and consistency of the heat.

Ferocactus gracilis - Fire Barrel Cactus - Unfortunately Texas is also tough on the Fire Barrel, the winter cold (less than 20 degrees) will mark the ridges as frost will turn the ridges brown and the red of the spines fades rapidly perhaps because of alternating heat, cold and humidity.