Veg anywhere from 45-60 days. This is your call. I have vegged plants for 90++ days and then went to 12-12 and HPS for another 45 to 60 days.yo im new to this so, i understand 18/6 for the veg. and 12/12 to sex/flower. but i dont know exactly when to change lighting . is thier a specific week? how tall it is? number of blades per leaf? thank you ^^
You can actually grow on a 12-12 cycle from the start.You can change the time over to 12/12 to flower anytime you think is right. I don't think you can do it too late but you can do it too early. I have heard of people vegging for only two weeks and then changing it to 12/12.