when does one put plants on the 12/12 system ? when do u start fertilizer? my plant is 19 inches tall with just light.
I would put it into flower right away.You should have been using nutes all along.Start a flowering nute system as soon as you can.That is if you start flower immediately.
Your plants will start to flower when you put them into the 12/12 cycle.You want them to flower so you can harvest some buds. Peace