Right now I'm at around 14 hours and 20 minutes of daylight. My plants are beginning to flower, but some more than others. Now that you've told me about the sensitivity to direct sunlight I think I know why all my plants aren't around 8ft tall. I put most of them in direct sunlight and two in a semi shaded area. The shaded plants are the ones that are around 8ft while the others are between 5-6 feet tall.

Are you familiar with any of the strains I mentioned above? If so, do you think they will grow well outdoors? If not could you recommend me some strains that will do well outdoors.

Also, what would be the maximum amount of time that you would keep a plant on a 18/6 lighting period?