youre biggest problem even experimenting with this is that creatine is really not all that water soluable. It tends to fall out of supsension rather quickly and I doubt that the plant would be able to take it up quickly enough to even be effectively dosed.
There would be a massive amount of variable and the logistics of understanding dosage versus usage would be staggering.
Good luck though, if Thomas Edison had listened to everyone we would have never had the battery.