i belive root bound plants do more curling and show abnormal growth rather than yellowowing...sounds more like a nutritional problem. no photos and not alot of information to go off of tho...how tall are the plants and how old, how big os the pot? how frequent do you water and how consistant is your watering schedule. that will help every one help you as you may not need to stress them by repoting now...they get more sensitive as they matrure:thumbsup: