on the forum i have seen farmers who grew about a pound in one gallon - giant plants! you should see what they can grow in a solo cup!
if you are aware of the issues you can overcome many of them. basically you grow an "air" plant! lol
but yes, pot size can help control size. with autos you can sort of control the length of veg using pot size. photos, you can grow a monster in a 20 gallon (youd need a 30 foot ceiling!).
as for figuring out exactly how much involves far too many variables. im experimenting with pot size (mostly concerning autos and veg time) now and find that a good guess is about 20% bigger from 1 gal to 5 gal, from 3 gal to 5 is not so distinct. i can tend/ignore and cause a greater difference.
one consideration is strain, some grow tall and if indoors might actually grow bigger (as to yield) in a smaller pot. you can pluck and pick at them to make them fit the environment and yield more than if left to their own devices.
try a grow with the same strain in the same soils but in different pots. you will learn a lot!
i had no idea that the autos could be slowed using pot size (or sped up... but why?) till i started and then had to dig out the info (not a lot of science on cannabis). but the pot size run is showing me lots of things about growth and space.
