I have vegged for 7 to 8 weeks and am ready to start the flowering phase. My lighting is 6 100w cfls 18/6 from 4am to 10pm. I am doing a closet grow and am concerned about the small amount of light that could come through the door during the flowering stage. Would my plants react negatively to a sudden lighting change? Id like to go 12/12 from 7am-7pm. I have always heard not to change the dawn time though...
Youll be totally ok. Many growers leave their plants in dark rooms for 24-48 hours before flowering to help "force flower". My suggestion would be to do something similiar to this. Wait til your ready to start 12/12 then wait for the night before when the lights go out. Use this dark time to switch your timer to the new 7-7 time and all should be gravy. Hope that makes sense basically wait til 10pm your lights should go out and then change the timer to start at seven the next day on 12/12. Any Q's let me know!
You will be fine. I always switch my times come summer. During the summer I run my shit at night. Helps control temps. Never had a problem when I changed things.
You can find 150 Watt hps for 60 bucks online then change most or all of your cfls to warm white bulbs to supplement