Are ye serious? I'll assume you are, if they are outdoors it requires day length to grow shorter, in the fall this happens =).
If they are indoors the lights should be set to 12 hours on /12 hours off and have total darkness when the light are off.. The buds grow from the little armpits between the stems and the leaves.
They are kinda like a flower. It takes forever for them to mature don't chop them down till 75% of the hairs are turned from white to brown. This is very important.