yo ive done that before growin sideways plants under my ex girlfriends house in the crawlspace
i dont know how or where ya growin ya didnt really give me a good description of the environment but long story short run a line cloths line or parachute cord work well about 6inches off the top of the pot or tub or what ever ya growin in place the pot on one side of the grow are and the light on the other then train your plant to the line that going to the light ill hook a picture up in not good at describing shit