it may be, but I only have experience with rootbound plants from friends, and on here, none of mine have been rootbound(I don't think) This is my first indoor grow, I usually grow outdoors, no pots, didn't have to worry about it. The clone I have flowering now is to test how big a plant I can do in less than a gallon pot. So far its ok, its not even 3 weeks in into flower and taller than my other plant was before I topped it. Hopefully someone else will post that has had experience with rootbound plants...