HOW TO BUILD YOUR OWN BIOACTIVE TERRARIUM

Written By Brittney Ricca

Terrarium Kit Assembly Guide

If you bought a terrarium kit, it likely has enough materials to make a second one. Just follow the instructions to measure the substrate amounts carefully.

Supplies

  • A transparent glass container with a lid

  • Leca or lava rock for the false bottom

  • Substrate barrier

  • Horticultural charcoal

  • Soil mix

  • Terrarium plants

  • Additional items (moss, rocks, crystals, figurines, sticks, etc.)

  • Optional: Beneficial insects (e.g., springtails, isopods)

1. Create the False Bottom

Once your transparent container is ready, begin by building the foundation of your terrarium. A clear jar is ideal because it allows light to penetrate effectively, supporting plant health and helping prevent mold and mildew.

Add a false bottom of leca or lava rock to your container. Use just enough material to cover the bottom by about half an inch to an inch.

This layer helps prevent root rot and creates a more natural water cycle within your terrarium.

2. Add the Substrate Barrier and Charcoal

Smaller kits don’t include a substrate barrier because it’s not needed. You can skip this step.

Trim your substrate barrier so it is slightly larger than your container. When placed inside, it should cover the entire base.

The substrate barrier prevents soil from mixing with the false bottom.

After placing the barrier, add a layer of horticultural charcoal on top.

Charcoal acts as a natural purifier, helping maintain clean, healthy water in your terrarium.

3. Add Soil and Plants

Now it’s time to add your soil. Pour in enough to comfortably cover the roots of your plants. Lightly moisten the soil with filtered water.

Plant your terrarium plants, arranging them however you like.

Once your plants are set, you may add additional elements such as moss, sticks, crystals, decorative stones, or any other accents you would like. Let your creativity flow!

Finally, add a bit more filtered water to your terrarium — but avoid overwatering. If water begins to pool at the bottom, you’ve added too much.

4. Tips and Tricks

To help your terrarium become self-sustaining, consider adding beneficial insects like springtails or isopods. These tiny helpers consume mold, mildew, and decaying plant matter while contributing natural fertilizer.

Place your terrarium near a window or in a location that receives natural, indirect light. Water as need, this will vary depending on the location you set it and the type of container you use.

Enjoy watching your terrarium grow and flourish!

Brittney Ricca