I have learned to never be swayed by color differences, as you said, environment has a lot to do with it. That could mean soil, fertilizer, temperatures, if a shot is taken in full sun or part shade as well as how a camera reads and displays colors. Some do really well with reds and purples, others need a bit of tweaking to get a more accurate rendition.
Between our two images, I would actually know they are one and the same as I look at those notched eye bands, they really look alike despite the slight color difference. :nodding:
If you are talking about the other image labeled as mine, if you enlarge it, you see the caption reads "Photo courtesy of Marietta Daylily Gardens".