I have a friend who wants to put the plants into flowering shortly after germination, determine the sex and then put the females back into veg. Will this work?
You could do it but why? Most of the time at 3-4 weeks veg you should have pre-flowers showing-Bud Merry Christmas
he can... It would probably be stressful to the plants and stunt them enough that they woulda shown normally anyway by the time i'd want to begin flowering.
the trick is to take some clones, then flower it out and determine if you wanna use the clones. that way you can have the genetics in veg, while you sample the plant and the smoke.
Ultra simple sexing. Put a piece of light blocking material over part of the plant for a few hours during the light cycle so that area get 12+ dark hours. Same shit you do with Poinsettias to get the red leaves to come out early.
We totally agree that this is the best route to go, just make sure and label the new clones so you can be assured of which plant they come from.