Materials

• Empty plastic bottle with a lid (at least 2 liters)
• Scissors
• Ruler
• Gravel
• Potting soil
• Bowl
• Water
• Plants
• Coffee filter paper (optional)
• Sphagnum moss (optional)
• Activated charcoal (optional)

Directions

1. Take a clean, empty plastic bottle at least 2 liters in size and with uncolored sides. Remove the lid, squash it flat in the middle and, using scissors, make a slit 8 inches from the base. Keep cutting until you have separated the bottle into two pieces and then make several slits around the top edge of the bottle base, each about 1 inch long.
2. Add a 1½ inch layer of gravel to the bottom of the bottle for excess water to drain into. Now, you’ll need some potting soil—enough to fill half the space left. Put this in a bowl and pour in water, a little at a time, until you can shape the wet potting soil into a ball, but not so much that the ball drips water. Now, place the soil in the terrarium. You could add a circle of coffee filter paper or some sphagnum moss first to stop the soil getting mixed up with the layer below.
3. It’s time now to plant. You need to have plants that can take the moist atmosphere of the terrarium. Mosses and lichens are a great start and can also add a lawn like feel to your mini garden. Try tiny ferns, baby spider plants and African violets. Just make sure nothing you plant will grow too large.
4. When you’re happy with your garden, put the top section of the bottle (with its lid on) over the garden. The slits in the side of the bottle garden base will help it fit. Now, sit the terrarium somewhere that’s light but not in direct sunlight.
5. As plants breathe, they lose water through their leaves and this will gather on the sides of your terrarium and eventually fall back into the soil as the temperatures and light levels drop. If there’s not enough water forming on the sides, you may need to add more or move your garden farther from the light. If there’s too much, leave the top off your terrarium to allow some to escape.

Tips: If you want to build a larger terrarium you could use an old fish tank with a lid. Don’t forget to add some interesting garden features—bridges, paths and even dinosaurs. That should liven up the place! You can add a half inch layer of activated charcoal (available at pet shops) above the gravel—this keeps the terrarium smelling fresh.