is it time yet?

one of my plants is seven weeks old and the other three are six weeks old.I still am not sure on sex, but the seven wk. old plant is 18 in. tall the other ones are around 13in. tall and I wanted to put them into flowering 12/12 before they get any taller b/c I know they will grow another 3ft. in flowering I must have missed the pre -flower but I also dont want to stress the plants out by sending them into flowering. please give me some advice

you wont stress em too much pushing flower now, they should be showing preflowers any day anyway.

oh yeah, you can put them into flower. that is a pretty good veg time for indoors. i have some that i have flowered after 1 1/2 weeks. some go 12/12 from seed

flower power they r big enuff theyll double n size in flower