I tuck all my shoots under the screen up until the last weeks of veg where i will start weaving the plants in the screen.
So that the screen will support the colas. Depending on your grow area and how big you plan on growing; lights and medium , grow area etc
. once i flip i will start to weave a few more times to take care of unnecessary stretch then allow them to grow up out of the screen once the screen is filled. and begin growing donkey dick colas.
This is an experimental grow in a SUPERCLOSET WITH A 400W LIGHT THAT I HARVESTED 10 ounces with a 2x3 screen