At the RSBG, we currently have three different collections of huanum in the garden and of blooming age. I collected these from three different mountain ranges in S Sichuan and adjacent NE Yunnan back in 1995. That is probably why we see such variation but they are primarily purplish or rose-purple and bloom in mid-April. A couple of years ago I was on a spring trip and once again found huanum far to the east in Chongqing and Guizhou. These had pink flowers and were in full bloom in early and mid-June (no it was not a late season, everything else was on schedule). Definitely huanum with the same calyx, habit, foliage, etc. Another mystery. In the 60s here with lots in flower already. If this keeps up there will be nothing left for May when the masses show up to see our “rhododendrums”.