Rain lilies

Question

The answer to my question about rain lilies didn’t help. The rain lilies in all gardens receiving my extra plants ALWAYS GREW AS PINK. Suddenly, I gave a bunch to a friend and they grew white. They weren’t pink and then turned white. She never saw any pink. I cannot upload my photo of the white lilies to show you.

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Answer 1

In that case it is probably a genetic mutation, known as a "sport": https://www.gardeningknowhow.com/garden-how-to/info/plant-sport-mutations.htm

There are some plants that change their flower color according to the pH of the soil they're in. I can't find any reports of this happening with rain lilies, but here's how it works with hydrangeas:
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/change-hydrangea-color.htm

And here is a discussion of other possibilities:
http://web.extension.illinois.edu/cce/news/news33191.html