IT probably just grew slower than the others for whatever reason...and then flowering was induced so that's what you got. You said it was in the same pot as another? The other plant was probably the dominant one in competition with your "mini-me"
...just my educated guess.

I once started an outdoor grow right into flowering season and it pretty much did the same thing...it stayed about 6''-7'' and flowered.
tha_green_ghost Reviewed by tha_green_ghost on . Smallest fully flowered marijuana plant!!! I just harvested the smallest plant ever. Total height of the plant was 6" from the root ball. Total harvest will be somewhere around a gram (dried and cured of course). I do not know the strain but it looks and smells very good. Is it a certain strain that grows like this? I grew it in the same pot as another plant and had a third in its own pot. The other two plants surpassed the little guy "Mini Me", very quickly during vegging. I almost cut it out when I induced flowering but I thought what Rating: 5