It all depends on the strain of MJ, the soil you use, the nutes you use, and the general care a person puts into the plant. It is an impossible question to answer. Anything could go wrong during the growth pattern. You could overfeed, underwater, underfeed, root rot, root bound...anything could happen and asking us to answer that question, is a total shot in the dark.

You have to remeber these growers pulling off 4lbs a plant are professionals and use the highest of the highest quality.