What size of pot?

Hi guys
I have a small grow room 40 cm x 40 cm x 100 cm and for light I use a 200 w CFL. For a time I have been growing my plants in hydro but everytime they get to tall. I bend and twist them and they still get burns from the lamp.
My next grow will start in a couple of weeks and will be in soil.
Do you have any suggestions to what size of pots I should use to keep the plants shorter?
I'm a big sativa fan and they are tall plants.

Best

i have the same problem was gonna post a thred like this in a couple of weeks, i was thinking of looking for plastic storage boxes that just fit in the floor of the grow room but mayby about 15cm tall and drilling some holes in the bottom and putting them on trays, the roots would then still have a fairly large volume but not much depth. would this be bad for the roots? having to grow sideways instead of upwards? would give them about twice the volume of the pots there in now and would give the plants about 15cm extra headroom

oh and im gonna get some chickenwire and use the scrog technique, mayby you should give that a go?

Obviously you should top them (cut top branch/es off if they get too tall, forcing growth outward, do this in veg stage NOT in flower. If I were you get pots with plenty of room (look around in grow journals for appropriate sizes) and just make sure you top the plants and/or tie down branches to get the shape of plant you like. There's loads of threads already on this. Good luck.

just lst and they wont get to big or get thc bombs and put them in 12 12 from seed, b done in bout 8 - 9 weeks, i use 3x 200 enviros