Rob Roy
Well-Known Member
The color of the bud is genetic, not from stress.
Mostly. Trichome and pistil color I think is genetic, but leaf coloration can be an effect of lower temperatures.
While some plants seem to go purple without any cooler temperatures, others, exhibit the purpling effect more as a response to lower temperatures and if the temperatures aren't low enough to trigger it, they don't "purple up" as much, or not at all.
Anthocyanins, the magic stuff in the plant that makes purpling, red and blue shades, tend to accumulate and present when the plant experiences reduced temperatures. The same strain being grown outdoors in the fall may get purple towards the end while their sisters grown indoors under more constant warmer temps stay green since they never experience the temperature drop.