lolz
trimming the roots is probably the best way to stunt growth.
besides that just dont give it nutes, keep a small light like one 42w cfl or one floro tube over a foot away, top the fuck out of all of it, keep in 24 hours of light to keep it shorter.
remember, durring the day (light cycle) is when the roots gather energy and they dont stop gathering energy (growing) untill the energy is cut off (light turns off). when this happens its time for the plant to use its pent up energy by sending the plant on a small growth spurt, so the roots grow durring the light cycle being on and the actual plant grows during the dark cycle.
keeping it in 24 and trimming the roots is your most important thing, and dont forget to top the shit out of it!
go to the corner and read a few modern cannabis books buddy, you just gave all kinds of TERRIBLE advice. Furthermore you said trimming roots was bad and then @ the end you said dont forget to keep doing it. Do you know what your talking about?
I keep 2 fluro t12's over a mother plant 5 inches away from her tops, I also Lst those tops to be equal or as close as I can get to even canopy level to make most use of the light.
1 tube a foot away is nearly non visible to plants.
Roots do NOT grow In the light period. They grow primary @ night, this is where the hormones called "auxins" come down from the very top shoots of the plant to promote root growth the most. A quick google search on that term should show you this to be true for yourself.
If a plant has problems with its roots not being strong a dark cycle will help it build roots faster than 24 hr light does. A 24 hour light is used in veg for faster veg times for the same growth that you would get in a veg time with a dark cycle.
While trimming roots to a plant Wont kill it if you dont trim too much off so that it cant get enough food, it stresses the hell out of plants like one wouldent believe.
Plants getting root bound is a myth as long as they get fed correctly. The reason that people notice stunting with soil plants is because their soil becomes depleated of nutrients after a while and the additional fertalizers that they have been giving a plant are then not enough to sustain it alone.
Plants roots primary function is to get nutrients, if you provide all that those plants need as far as nutes and do so right, then you will never notice any stunting because the roots dont have space to grow... I grow 3 to 4 foot plants in half gallon grow bags indoors and grow those in veg or in flowering too.
If you must transplant a plant because you want it to recive more nutrients from the soil a larger container isnt always desired for many of reasons. In those cases I remove them from their pots and hold the rootball in both hands by the bottom while dunk them up and down un a 5 gallon bucket filled half way with water . The dirt should let go of the roots that way.
peace and hope this helps your grow Matty.