Fill a glass vase half full of water. Add 40 drops of food coloring to every 2 cups of water used. A few more drops may be added to gain a deeper color. Add a little granular plant food to keep the roses fresh.
Cut across the bottom 2 inches of the roses stems diagonally. This will provide a pointed end.
Place the roses into the vase of water, stems first. When multicolored roses are desired, the stems may be cut in half, with each section placed into a container that has a different color of dye added. If using this method, be careful not to break off the stems.
Experiment with the colors to create the perfect shade.
Place the vase of roses in a cool place since the process will take a few days. When the color of choice is achieved, remove roses from the vase of colored water and create the arrangement as desired.