Eyerton wrote: I need to know what causes the cells to change color?
How and why were the chloroplast effected? What are the most common cells? Why do they change color, does the die stow away with the water when it is absorbed in the cell?
Your questions imply/assume things which your experiment probably doesn't prove or disprove.
From general plant biology, you've probably learned that most plants absorb water from the soil they are planted in and that the water goes up the stem and through veins in the plant to all parts of the plant.
By observation, you saw that the red food coloring mixed into a solution with the water. If you were to put a tip of a piece of news paper or a cotton rag into the colored water and leave it there, the water and food coloring would be absorbed by the paper/rag and would wick up the paper/rag. Once the water dried, the red dye would be left. You don't have to have living cells for that to happen.
To answer your questions, you would probably have to disect a dyed flow and study it under a high power microscope to determine if the dye actually made it through cell walls or if it was just on the outsides of the cells.