When should you preflower?

i have two plants. one is 6 inches tall, the other 3.5 inches. They also each have alternating nodes. Should i preflower at 8 inches? or should i wait.

come on people! help me out here.

Pre-flower just happens like the sun rising. Are you meaning flowering? When to switch to 12/12?

yeah. to force it so i can tell the sex.

You have to take a clone which is hard on a small plant. Why does matter what sex they are? Just flower when you want to flower and you'll find out soon enough.

since you are wanting to force for sex: now.

hmmmm. will forcing stunt the growth? i love my plants. i don't want to ruin them haha