Changing the Color of Flowers
In this experiment, the children will realize how vital the roles of the roots and the stems are to the plants.
The materials needed are 6 white carnations, 6 plastic cups, food coloring, knife and water.
Fill the cups half full with water and add 20 to 30 drops of food coloring in each cup. Use different color for each cup. You can choose any color you like. This time the more food color used the better.
Ask an adult to help you trim the stem of each flower to make a fresh cut. In the case of cut flowers, it is very important for the stem tubes to be filled with water. The reason is this, no water can move up if the stem tubes are filled with air. What most gardeners and florists do is, they cut the stems under water to prevent the air bubbles from getting in to break the tube of water causing the lovely flowers to wilt faster than they would.
Now, it is time to place the freshly cut white carnations in the cups of colored water. One carnation for one cup of colored water. But, save the two other carnations for the next step. You can make predictions as to which color will be soaked up next and how long will it take to do it.
Ask an adult to help you with the handling of the knife as you slit the stem straight from the middle downwards. Take one half of the stem and place it in colored water and the other half on different colored water. This trick is called Split Ends. Again, you can make predictions as to which colors will be soaked up first or will the two colors mix to create another color. Always remember to keep the ends of the stem wet and make fresh cut on the ends.
Try checking back every now and then to see how your plants are progressing. Sometimes, it may take up as much as 24 hours for the colored water to reach the white petals. At the end of your experiment, do not forget to examine all the parts of the plant like the stems, buds, leaves and petals to find every trace of color.
In this experiment, it has been noticed that plants get their nutrients from the water using their roots drink the water then it travels to the stem into the leaves and flowers where it makes their food. In this case, even when there are no roots, the stem is still drinking the water to provide it for the leaves and flowers.
Putting food color in the water of the plants does not harm them. But like colored dyes, chemicals that pollute the waters can get into the soil and ground water, contaminating our vegetables and plants. Some pollutants and chemicals, just like the colored, may even travel up the plant and affect the way the plant grows.