Introduction: DIY Sealed Terrarium (3 Steps With Pictures)

So why build a terrarium? Sure, it is a way to keep plants in your house with minimal effort and space, but what I find most intriguing about terrariums is that they are completely self sustaining. After the first time you give it water, you never have to again. It reuses every drop of water infinitely! That's right, zero maintenance mini gardens. Ready to make your own terrarium? Let's see what you will need.

Note: There are 2 types of terrariums, separated by 2 key differences. Open-air terrariums can only support succulents, while sealed, or closed-lid, terrariums can support a wider variety of small plants. Also, open-air terrariums require you to water them very minimally, while sealed terrariums never need water after the first time. This instructable is different from others because it teaches you how to make a sealed terrarium, while many other terrarium instructables are for open-air terrariums.


  • small pebbles (enough to make a 1 inch thick layer in the container)
  • activated charcoal (enough to make a 1 inch thick layer in the container)
  • potting soil (enough to make a 2 inch thick layer in the container)
  • small, slow-growing plants that like moist dirt and humid air, like small ferns (I used a Korean Rock Fern)
  • Reindeer Moss
  • 1/2 gallon mason jar or other similarly sized glass container


  • small clippers to shape the plants

Once you have all that, go ahead and move on to the next step!

Step 1: Make Your Terrarium Plant-friendly

Before you can put plants and other decorations in your terrarium, you have to make sure that the plants won't die. To do this, you will need to place your layers of pebbles (to provide drainage), activated charcoal (to filter the air), and potting soil (that one should be obvious). Make a 1/2 to 1 inch deep layer of pebbles, and then cover that with the same amount of activated charcoal. Then add a 1 to 2 inch deep layer of potting soil. Once you have done this, you are ready to move on to the next step!

Step 2: Place Your Plants

Before you put your plants in the terrarium, you will need to make sure you don't have too many plants so that they are not overcrowded. You may even have to trim some of your plants to make sure they fit. Create divots in the potting soil for the roots, and then pat down the soil around the plant's roots. Place a layer of moss about 1 inch deep (or less, if your plant is low to the ground) covering any exposed ground. Gently water your plants, making sure to stop as soon as the soil is evenly damp. If you want to, you can mist the plant leaves to give your terrarium a head start on creating a humid environment.

Step 3: Finding the Right Spot for Your Terrarium

First, double check everything is how you want it, and feel free to add miniature people and other small models/sculptures to customize your terrarium. Make sure your terrarium has an airtight seal and then place it out of direct sunlight (the glass makes the sun's rays stronger) but in a well-lit area.

CONGRATULATIONS!!! You just just made your very own terrarium! I hope you enjoyed my instructable!