Fertilizer Runoff Demo

📋 What You'll Need

• •A baking pan or shallow tray
• •Dirt or potting soil
• •Granular fertilizer OR a substitute like sprinkles
• •A watering can or cup with water
• •A clear cup to collect runoff
• •Food coloring (optional, for visibility)

👣 Step by Step

1. 1Slope the tray slightly by propping one end up on a book.
2. 2Spread soil across the tray and sprinkle fertilizer (or sprinkles) on top.
3. 3Place a clear cup at the low end to catch runoff.
4. 4Slowly pour water across the top of the tray like rainfall.
5. 5Watch the water flow downhill and collect in the cup.
6. 6Observe the color and clarity of what ends up in the cup.
7. 7Try it again with no fertilizer and compare the two cups.

🔍 What to Observe

• •Did the runoff cup change color?
• •What does this show about what rain carries into the lagoon?
• •How could you slow the runoff down?