YES. It will work. I brought this concept up a few months ago but it never really caught on. It took alotta research and a few mistakes but I found out that food coloring was safe to use, but it's made up 90% coal tar derivatives and will stunt growth in its early plant life. I reccomend watering with 1 whole little squirt thing (tiny little bottles each color comes in) to a gallon for the last couple of watering before the final flush. And wuala! Purple haze! Just throw in half a red and half a blue to a gallon for purple, half yellow half blue for a rich rich green, etc etc.. It's your choice!