It has been very hot here in Mesa, AZ. 113 today. 113 yesterday. 111 the day before that. I water my trees every second day. I will water them after I post this. I know these plants will bounce right back after being watered. I also know that many advocate providing shade. I feel that allowing the plants to experience the full sun will help them in the long run to be strongly rooted and well adapted.
It seems variety plays a role in how well a plant can tolerate the heat and sun all day. Here are the photos. Judge for yourself how well each variety does in this intense heat. They all receive the same care.
Black Mission NL
Col de Dame
Violette de Bordeaux
Joe's Jersey
LSU Purple
Hardy Chicago
Desert King
LSU Gold
Barnissotte
Black Madeira
I observe that many of the varieties have put out leaves with highly serrated edges, which I believe is some sort of adaptation to the intense dry heat.