i have a buddy that had 1 plant, the plant was about 2 and a half feet tall at full. he got over an ounce and a half from it, and he barely knows what hes doing at all.
he didnt have proper lights, he picked them up from wal mart, not even the right spectrum or wattage, just some flourescent lights. he didnt know what nutrients to use, didnt know what soil to use. all he really did is water them and feed them nutrients. and he got almost 2 ounces off it.
of coruse because of his lack of experience, the bud was crap. he just bought stuff after that, and he would sometiems smoke the stuff he had.
but that might give you some idea on yield. this is actually my first controlled grow, so im waiting to see what kind of yeiled i will get.
i have two plants right now that are only about 30cm high going into flowering. well that was two weeks ago, they have grown to about 40cm now after 2 weeks flowering. but i think i will get a decent yield from them.