Name: Anne Summerville, SC (Zone 8a) Only dead fish go with the flow!
It's not unusual at all for double H. rosa-sinensis to go from single to double on the same plant. A lot of my doubles do that, like Love Story. Exact same plant produced both blooms.
Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so.
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