12/12 mean that 12 hours light on and 12 hours light off (completely dark). The earliest you can do it is as soon as your plants have 3 set of true leaves.
cnd411 Reviewed by cnd411 on . Force flowering??????? I got some quick questions that i need answered as soon as possible plzzz. I hear people on this site mention you can force flower by setting you lights to 12/12 what exactly do these numbers mean??? What's the earliest I can do this? Also for lighting would 2 150 watt light bulbs work to get a plant? I don't care if it wont be the best quality i just want it to be able to survive. Please answer as soon as possible. Rating: 5