Quote Originally Posted by texas grass
personal preference
power consumption

i like 18/6 cause it uses less power and its more natural for the plants
Throughout my research of the stomata to try to figure out how we could manipulate it for our own benefit I found something interesting.

The plant will set it's clock based on the number of hours it receives light/dark.

Now what was interesting was this.. Was that even if the plant is in an enviorment that has lighting 24/7 the plant would develop it's own clock and actually go to sleep on it's own. This was indicated by stomata closure even during direct light after receiving light for 20 hours.

However for our purposes this is only useful to know for vegetative state as the 12/12 cycle is needed in flowering to promote certain hormones.

With that said... Use 18/6. Less electricity and the plant is going to rest on it's own even if you have your lights on 24 hours a day.