i will be changing over to flowering sometime in the next week my plants are around 12" at the mo i just wanted to know can i go from 18 hrs light - 12 hrs dark or do i have to go 12 hours light - 12 dark at the mo they turn off at 6pm this is so i can have my lights on during the day otherwise they will be on 12 midnigt - 12 noon . and i want them on 6 am - 6pm any suggestions? will this stress the plant out if i go 18 hrs light - 12 hours dark then 12 hrs light an so on ... im new to this thanks
The day you switch, you can give them an extended dark period until the time you want the lights to turn on every day. (6am?) Then keep the lights at 12 /12. (6am - 6pm) Does this answer your question?
yeh thats what i meant , so i can just give it 18 hrs light then 12 dark . so it is a 30 hour day? then just go to 12/12 from then on and this wont stress them out?
Plants start flowering based on the amount of DARK hours they get not light hours. So, with that said if you want to start your 12/12 from whatever time period it does not matter as long as you consistantly give 12 hours of dark time. That is, if you for some reason decide you want to start your 12/12 as soon as your lights turn off it's fine. In fact it doesn't matter when you start your 12/12 as long as you start giving 12 hours of light. In my opinion it's not OK to give your plants an extended dark period. Like I said, it doesn't matter when you flip the switch, just as long as you make sure the dark period is 12 hours long. If for some reason you want to flip the 12/12 after your plants have only had 4 hours of light that's OK just keep the constant the dark period.
NP. I just don't think a lot of people know that. I completly understand if you want to adjust when your 12/12 period starts as I would too just so that 12/12 period can be when I am most apt to be awake and home, or for some people maybe the opposite. If your plants normally turn on at noon when vegging, but for some reason when you start flowering you want them to go to sleep at 4, it doesn't make no difference, as long as the 12 dark hours is a constant . Glad to help.