Need Some Help With Dixie Cup Grow

Hey everybody, I have some plants growing right now there about 3 inches tall and there in red dixe cups, I want to know how tall I can let them get before I have to transplant them. I would really like to keep them in the cups the whole time if I can without them dying.

Has anyone done this before??? I need some input from anyone with some experience

THANKS

yeah- red dixie cups have seen an increase in bus too!! If holes are put in bottom, our exp. is that they need h2o often. We do this :Wait until dry, tip upside down, gently remove soil plug. If you see roots bound go ahead and transplant to lager container. They will love ya for the extra room to expand root mass!! Good Luck!!

i would transplant it at least into a 12 ounce cup in a week