What to do:
Fill the glass or jar with water until it's half-full.

Add five to ten drops of food coloring to the water and mix.

Place the stem of a flower into the colored water

Let the flower stay in the water overnight, or until it begins to change color.

What happens:
The flower petals attain the same color as the food coloring.

Why this happens:
Water moves through tiny tubes within plant stems. In this experiment, water and food coloring have moved up the stem to the flower, making it change color. Florists use this trick to create flowers with unusual colors, so that's why you'll sometimes see green carnations being sold around St. Patrick's Day!