Yeah, i agree that you can't have a plant that's "too big" outside. I'm planting mostly hybrid plants that won't get bigger than 6 or 7 feet tall at most. If you want one of those plants that grows 20 feet tall, you'd have to get a pure, tropical sativa like a pure "haze" or a pure "thai" strain of some kind. I think those are the ones that grow really big.

I am going to top a few of each strain and let a few of each grow normally to see what kind of difference it makes around harvest time.

Peace!