Struggling with Saguaro — would appreciate advice

I want to be honest: I'm not getting great results with Saguaro and I'm not entirely sure why. slow growth frustration for impatient growers has been a recurring problem despite my attempts to address it. I've been focusing on watering sparingly and only in the active growing season based on everything I've read.

spectacular but brief blooms that can appear overnight is there in glimpses, which tells me the plant has potential in my conditions. I have it in a dry garden rockery or gravel bed which might not be ideal. offsetting and pup production in spring showed some improvement. Two stars for now — not the plant's fault, but not a success yet. I'll update if things improve.