Looking on Google Scholar using "influence of temperature on anthocyanin" or similar search terms yields lots of hits, many fairly abstruse and most dealing with fruits. I used to grow a dahlia 'Crichton Honey" that had a lot of red blush in the blooms in spring and fall, but in really hot weather the blooms were almost completely yellow. So that's another data point, albeit anecdotal. Just as an example from the abstract of one paper:///Anthocyanins/ are flavonoid compounds that protect plant tissues from many environmental stresses including high light irradiance, freezing temperatures, and pathogen infection. Regulation of anthocyanin biosynthesis is intimately associated with environmental changes to enhance plant survival under stressful environmental conditions. Various factors, such as UV, visible light, cold, osmotic stress, and pathogen infection, can induce anthocyanin biosynthesis. In contrast, high temperatures are known to reduce anthocyanin accumulation in many plant species, even drastically in the skin of fruits such as grape berries and apples. On Sunday, March 27, 2022, 05:19:06 PM EDT, Steve Marak via pbs <pbs@lists.pacificbulbsociety.net> wrote: Bob beat me to that comment, but it's widely accepted in orchid circles that cooler temperatures, especially in combination with brighter light, yield more intense flower colors, sometimes dramatically so. I haven't seen (or looked for) any research on the topic, but I've seen multiple flowers that developed in different temperature conditions that were so different in color I'd never have believed they were from the same plant if I hadn't had it in front of me. But I think it's quite nice as it is. Steve On 3/27/2022 3:04 PM, Robert Lauf via pbs wrote: > I agree with Arnold, and my one suggestion, based on complete ignorance of Cyrtanthus but observations of many other things, is that much cooler conditions can enhance the production of anthocyanins. So moving it outside any time the temps are above freezing might bring out more of the red. Just a thought. > And it does have a subtle beauty, nicely captured in the image. > Bob > > > _______________________________________________ > pbs mailing list > pbs@lists.pacificbulbsociety.net > http://lists.pacificbulbsociety.net/cgi-bin/… > Unsubscribe: <mailto:pbs-unsubscribe@lists.pacificbulbsociety.net> _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/… Unsubscribe: <mailto:pbs-unsubscribe@lists.pacificbulbsociety.net> _______________________________________________ pbs mailing list pbs@lists.pacificbulbsociety.net http://lists.pacificbulbsociety.net/cgi-bin/… Unsubscribe: <mailto:pbs-unsubscribe@lists.pacificbulbsociety.net>