- 1). Use white roses, or ones with a light color. They should be fresh. Roses that have opened will not use as much water, and so will not take up as much color.
- 2). Stir floral preservative (you can get this in packets wherever you buy freshly-cut flowers) into warm water so that the roses will be fed and so last longer, and will also avoid bacteria that might block their stems.
- 3). Use one container of food coloring (which is about .25 of an ounce) for each cup of water that you have put into a vase.
- 4). Fill a bowl with warm water. Cut about a half an inch off of the end of each rose's stem while holding the stem under the water. This will help the rose take in water by preventing bubbles from entering the stem tube.
- 5). Put the newly cut rose into the vase with the floral preservative and food coloring mixture.
- 6). Check on the rose every few hours if you'd like to watch how the petals are changing color. The change should happen quickly. After 24 hours, the rose should be the color of the food coloring.
- 7). Try splitting the end of the stem into two pieces, then putting each end into a different container of food coloring mixture. Both colors will travel to the rose's petals.
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