When the temps are consistently over 105º here, they turn white... not sure about your house... unless you like it REAL hot in there! :D

The change of color is too complex to suss out without doing controlled experiments. Fertility certainly is a factor, since repotting a stock plant whose flowers have gone white will bring back red flowers. So will applying fertilizer to garden plants. Day length and temperature are also factors. How they all interact sounds like a good project for a botany graduste student.

Man, I was gonna just post this very question! I'm not even a salvia fan really, but when I saw 'hot lips', I decided to break down and get it. And wouldn't you know it, it went all white on me. It was gorgeously bicolored when I got it, and has since only bloomed white. We don't even get into the 80's really, let alone 105, so I don't think it's heat stress, LOL. (I live outside San Francisco, CA; where it hovers around 65-70 degrees for most of the year) I'm ready to give it the old heave-ho if it doesn't start showing me some color...

Amanda 'romando'

Amanda,
I don't have this particular salvia yet but from what I have been told by those who do have it, it will change color again. So if you are intent on giving your plant the old heave ho you can heave it my way. I am patient and can wait for it to change color LOL!

Penny

Mine changed too. It was red and white when I bought it early summer, turned totally red right away, and just recently it is mostly white, with a few bicolors. Very interesting !

Texas Carol

I had one planted in the ground when I lived in north Texas. It bloomed bi-colored when the weather was cooler and went solid - mine went mostly red, but some white - when the weather was hot in the summer. It also bloomed profusely in the cooler weather, and much less so in the heat of summer.

My Hot Lips plant is happily putting out bicolored flowers even now! What a great plant!

Joseph