red leaves

these were taken just a couple of minutes seen RED LEAVES on just one plant. Could this be of low temps, a sign of getting ready for harvest...... Thoughts or opinion ??

Hi, I'm Pharazir, a new member, and I've got a question. It may seem foolish but it seems worth asking about. After all, these are our babies ... We've got several plants whose leaves have, in the last couple of weeks, started turning red or even magenta in color. I've read several postings...