Period of Darkness before flowering stage?

I am about to begin the flowing stage and I have read, I think, that you should put your plants in 24 hours of barkness before switching to 12/12.

I am at 18/6 now (for veg). Do I turn the lights off for 24 hours first, then switch to 12/12?

Thanks in advance for your opinions.

Some do, some don't. It's entirely up to you. Those that do the 24 hour dark thing claim it helps to speed up sexing and/or flowering but the plant will decide in the end.

I have done it both ways and I saw no difference at all.

from what ive heard the 24 hour way was the way to go, sorry tho...no experience yet! ha
good luck

Next time they are off leave them off 12, then on 12 etc.