Usually some of my succulents, whether Semps or not, turn red when it gets cold stressed here, when overnight temps start hovering 50F and below. Of the few Semps I had and tried, Semp Rubellum 'Mahogany' turned red, and Semp Sir William Lawrence, had reddish tips when I got it in late Spring and it turned all green as our hot and dry conditions ensued towards summer. Once it gets way too hot, either they bolt or get too dried out or go mushy if I got too engrossed keeping them moist to endure summer.
Our temps here go in the extreme during summer so at very dry triple digits, so either the succulent goes somewhat dormant too, and returns vigor once Fall arrives and with the cooler temps nice colored hues.
