How so? I mean I can tell you the dates that mine have historically bloomed, or even broken dormancy and then equate that to a week type cycle. It would probably work for up here but doubt down there.
Or did you mean colors. That is sort of subjective. So could we just submit the colors the national peony judges them buy to keep it more objective. I do that for my dahlias using the ADS data base. As well as their rating for size of bloom, etc.
