Earthworms are amazing animals that are essential to a healthy soil system. Did you know that earthworms can live for two to eight years and that they eat up to one-third their weight every day?
Worms are major decomposers of decaying matter. They mix and aerate the soil. In addition, their body waste contains nutrients that plants can use. Because they live under the surface of the soil, we are often unaware of the important work they do for our yards and gardens.
Here is a simple earthworm habitat that you can create with your child to observe how earthworms move and improve the soil.
Items you will need:
- 1 clean 2 liter plastic bottle, with the label removed
- 1 smaller bottle, like a 500 ml. water bottle with a cap
- Sharp knife
- Plastic cup or spoon
- Sand, small pebbles, and soil
- Water and a measuring spoon
- Crumbled dead leaves for worm food
- A few earthworms
- Scotch tape
- Food wrap to place over the top of the bottle
- Dark paper to wrap around the outside of the 2 liter bottle
Once you have gathered your materials, you are ready begin the first step. A responsible adult should slice the 2-liter bottle with a knife at the point where the neck of the bottle begins to narrow. Then use the scissors to cut around the bottle and remove the top. Next, place small pebbles or sand in the bottom of the bottle to stabilize it and to create a base for the water bottle. Fill the smaller bottle with water and screw on the cap. Place the smaller bottle inside the larger bottle. The reason you are using two bottles is so you can observe the worms’ tunneling activity. In a larger container the worms would most likely gather and hide in the center of the bottle.
Now you can begin to fill the 2-liter bottle with layers of soil and sand. Sprinkle 4 or 5 teaspoons of water on top of the layers, and add a layer of dead leaves. You are ready to add two or three worms.
Worms breathe air through their skin and prefer to work in darkness, so in order to finish your worm habitat, you must cover the top and sides of the bottle. Cap the worm habitat with a piece of food wrap in which you have cut vent holes. Tape it to the bottle with scotch tape. Wrap a piece of dark paper around the sides of the bottle and tape it together. Place the worm habitat in a shady place away from direct sunlight. You will need to add 2 teaspoons of water everyday to the bottle. Be careful not to add too much water!
The worms will set to work. In about two weeks you can remove the dark paper to observe that the worms have made tunnels through the layers of sand and soil and mixed the layers. These tunnels are similar to the tunnels that worms create in your yard and garden. The worms’ tunnels enrich, loosen, and aerate the soil. They also increase the soil’s water holding capacity and provide channels for root growth. Be sure to carefully release the worms into a safe place so they can continue their valuable work underground.