I’ve never heard of those techniques to induce colors but I could see the ice method more than the bark strip, but a lot of growing has gone on before I got back into it for real.
I’m pretty sure I read that the Colombian Gold was sun dried and maybe on the stalk, too. I’ve dried some in the sun and it gave a cross that I made an almost red color, like old Colombian Red. I also had one that turned very yellow/gold.
I think colors are genetic since some strains will go all green, even with sisters throwing colors. And some strains won’t turn any color no matter how much cold you give them.
Afghans… = color, heh… in my limited experience.