@ True North - I think the greater issue is keeping the beds well drained in winter rather than summer heat. Heat does appear to be an issue with C. flavum, but not as much with C. tibeticum.
As for looking for domestic sources for Cyps, that is not a bad idea, but most vendors are buying their plants from just a few European growers anyway, meaning that “everybody” that sells Cyps, in particular the hybrids, are getting them from the same source. Getting plants from Hengduan Biotech gives you a chance at getting some very unique plants - straight from their native source. Also, you can be assured that the plants in question are true to form, not look alikes. You’d be hard pressed to find a reliable source of some, notably the aforementioned “amesianum” form of tibeticum, the lovely large flowering white based colored tibeticum, true calcicola, bardolphianum, plectrochilum, yunnanese, etc. I agree, if you want hybrids, then European sourced plants may be best, but for the pure species, I’d prefer those straight from China.
