#3195. Plant Stem - Do Red and Blue Make Purple

Science, level: Elementary
Posted Mon Aug 9 06:06:25 PDT 2004 by Carla Dearth (cdearth@accnorwalk.com).
New London Local Schools, New London, OH USA
Materials Required: 3 white carnations, 2 straight-sided plastic jars, read and blue food coloring, water, and knife
Activity Time: about 30 min.
Concepts Taught: Stem carries water to leaves and flowers

1. Review that water is taken into the plant by roots.
2. Talk about water is carried through the stem to the leaves and flowers.
3. Fill the 2 jars with warm water.
4. Add red food coloring to one jar and blue to the other. Make sure the color is dark. Other colors can be substituted.
5. Put a carnation in each jar.
6. Ask the students what they think will happen to the flowers.
7. Take the last carnation and split the stem up to within about 1 1/2 inches or the flower.
8. Set the 2 jars side by side.
9. Ask the students what they think will happen if you put one side in the red jar and the other side in blue.
10. Put one side in the red jar and the other in the blue jar.
11. Check them for the next few days.
*** Caution the children not to touch the jars or flowers, because if the stem breaks the experiment won't work.