This may be a really stupid question, but here it goes............ I will be starting with "bag seed" and am wondering how much harvest to expect off each adult plant after drying ?????? How is it even estimated ???? I am thinking of going with (4) of the 12" 3gallon pots cause they will fit into the space nicely, but, with this being my first grow, how do you estimate what you MIGHT get in the end ?