Giant Celery Rainbow Walk Challenge
⚠️ Safety Warning
Adult help needed for cutting celery. Do not eat the dyed celery.
All experiments require adult supervision.
Materials You'll Need
Gather these 5 items before starting
💡 Tip: Check off items as you gather them to stay organized!
Step-by-Step Instructions
Follow these 8 steps carefully
In this challenge, fill 4 clear glasses halfway with water.
Add 10+ drops of different food coloring to each glass — use vivid colors.
Cut the bottom of each celery stalk at an angle for better water absorption.
Place one celery stalk in each colored glass.
Check the celery every few hours and observe changes.
After 24 hours, the leaves and stalk will show the color of the water!
Cut a stalk in half crosswise and look at the colored dots — those are the xylem tubes.
Try splitting a stalk partway and putting each half in a different color!
✅ Remember: Take your time with each step and ask an adult for help if needed!
The Science Behind It 🔬
Plants drink water through their roots (or cut stems) using tiny tubes called xylem vessels. Water travels up through these tubes by a process called capillary action — water molecules are attracted to the tube walls and to each other, pulling the water upward. Plants also lose water through their leaves (transpiration), which creates a pulling force like sucking through a straw. The food coloring travels with the water, making the path visible. When you cut the stalk, the colored dots you see are the individual xylem tubes! Big trees can pull water up over 100 meters using this system! The physics behind this experiment was first discovered hundreds of years ago and is still being studied today.