Control the stretch
After the switch of light, the plant will bloom, but before showing buds, she will start to grow fast, often double or triple in size. It is called the stretch. Sativa dominant usually have a strong stretch (x3 x4 or more) whereas indica dominant have x2 or no stretch at all. If you grow sativa plants, make sure they don’t grow too high !!
During the stretch, plant will ask great amount of fertilizer, especially nitrogene (N).
If your plant starts to grow fast and tall, squeeze the stem with your finger just above a node on top of the plant. Press enough to hear the bark break, but also gently to don’t kill the bud. If it’s not enough, repeat the pinch in different points above several nodes.
You can also train the branches to lower them.