I live in a zone 8a area, but I grow them in a greenhouse for production (we were zone 7b but were recently reclassified by the USDA). I work for a nursery that does a lot of Semps so we're really trying to crank these things out this time of year (I don't want give anymore away than that online, but bonus points if you can guess were I work
). The two S. 'Bronco' in my previous photos were brought to my attention by my boss and I was at a loss to explain what was going on to him.
Here's some other photos of Semps in the same part of the greenhouse. Sempervivum 'Black', Sempervivum 'Fuzzy Wuzzy' and Sempervivum 'Oddity'. The former is doing a similar thing to S. 'Bronco' while the latter two are nice and compact like normal.