How To Make A D.I.Y. Terrarium with your kids.

DIY terrariums teach your child patience, science, and helps them grow into responsible adults.

Terrariums come in all shapes and sizes. You can add whatever plants or soil you want, including any little toys to give it a unique like of its own. In this article, we’re going to show you how to make a D.I.Y. terrarium with your kids.

This is a terrarium.

Notice how compact it is. It’s not in a 30 gallon fish tank, actually it fits right on a desk.

Now we’re not talking about sprouts in a cup. We’re talking about using our nerdy obsessive tendencies to creating a tiny universe unto itself. Muahaha!

It doesn’t actually take an omnipotent green thumb to create your own little ecosystem. Terrariums are easy to put together, materials aren’t hard to come by and with a little geeking out, you could have yourself a pretty awesome terrarium

Terrariums are, at their core, a clever way to get a child to do a science project that doesn’t leave your kitchen looking like the site of an epic baking soda/red food coloring battle. You know — the whole science fair volcano fail.

Power-hungry universe-ruling aspirations aside, terrariums really are little self-sustaining ecosystems. Making a terrarium with the kids is just a much cooler way to teach them about ecology and the inter-connectedness of creatures and the planet.

🪴 What You Need

All-In-One Kits

For those of you looking to get started as quickly and easily as possible then we recommend purchasing a kit that has everything you need. This is great for younger children or for those of you that don’t have the greenest of thumbs.

Purchase a container

This can be anything from a container made specifically for terrariums to an old fishbowl. First, decide if you want an open terrarium (above) or a closed terrarium then go nuts.

Here are several they we like.

---

---

If none of the above interests you, feel free to use a light bulb, a mason jar, or a vase. You can even use the tincture bottle from your collection of pre-1930s apothecary antiques! You know, whatever you have lying around.

Base

Sand – Nothing special here, just the stuff that comes from a beach or a sandbox. 

Activated Charcoal – Available at aquarium supply stores. 

Potting Soil – This should be a mix of regular potting soil and a well-draining potting soil like one designed for succulents.

Pebbles – Feel free to take care of this one at the aquarium supply/pet store, too. Pebbles that go on the bottom of a fish tank work great.

Damp Spaghnum Moss [OPTIONAL] – This is optional, but it helps keep the soil from falling below the pebbles. It also looks pretty cool, especially if you’re going for a hobbit-like shire-esque vibe.

Plants

Variegated Spider Fern

Your best bet for plants are ones that work well in a high-humidity environment. This is mostly true if you want a closed terrarium. I like these for both types of terrariums though because these plants are hearty and hard to kill, which is nice if your little gardener’s thumb is more brown than green.

Starfish plant (Cryptanthus Bivittatus)

Venus flytraps and other carnivorous plants are also a lot of fun. (If you have a kid who doesn’t find plants quite as thrilling as you do, this is the way to go.) Warning: These can be a little bit more finicky than the others on this list.

Spray Bottle

🤪 THE FUN STUFF!

OK, moss is fun on its own but when creating a terrarium with kids you might want to think about adding some friends.

Also particularly amenable to living in a terrarium are Ninjas, LEGO mini figures, and little plastic bugs. This is where to let your little nerd go crazy.

👩‍🌾 PUTTING IT ALL TOGETHER

1. Start with a 1-inch thick layer of pebbles in the bottom of the container.
2. Put a layer of activated charcoal on top of the pebbles approximately one-half inch thick. This will filter the water.
3. Put a layer of Sphagnum moss on top of the charcoal.
4. Top these layers off with a 2- to 3-inch thick layer of soil.
5. Poke small holes into the soil and transplant your plants or place seeds into the container. Take some time with the kids to talk about the design of the terrarium and how much space each plant might need.
6. Place any buddies, dinos, Yodas, or toy butterflies in the container.
7. Water in moderation and cover. Keep an eye on it. If it needs more water, then add. If you have over-waterers in your house (like I do), you may notice the soil is getting too moist. If this is the case, remove the lid from a closed terrarium to let it dry a bit. If you have an open terrarium, teach your little gardeners that water doesn’t always equal love. Over-watering your terrarium can lead to mold growth, and that’s a whole different and smellier science project you probably don’t want to deal with.

There are guides if you want to really deep dive into professional terrariums. Oh, and I feel it’s my duty to let you know that this exists.

SCIENCE!

Just because I want to teach my kids about biology doesn’t necessarily mean that I was paying attention in bio class when it was being taught to me. So for others of you who may have been checking out fellow students instead of checking on the Erlenmeyer flask, here’s a quick rundown of the science-y part of terrariums.

The ecosystem inside your container is a microcosm of the real world. You cause it to “rain” by watering the plants or seedlings. The water is accumulated in the soil and sunlight will cause this water to evaporate and form droplets along the sides and top of the container (condensation). These drops will grow larger, then fall back into the soil. This is a cyclical process (the hydraulic cycle) that will keep going as long as there is water and sunlight. This process is what gives the plants a constant supply of moisture and nutrients. It’s also known as a closed-loop system. The activated charcoal in your terrarium acts like a filter. As the water passes through the charcoal impurities are trapped so the water stays clean for the next cycle.

Terrariums also provide opportunities to talk about what pollution does to the cycle, other closed systems and bio-regions. For instance, when recreating Tatooine so your LEGO Luke Skywalker can feel at home, be sure to remember that after the Rakata razed the planet, drying up its riverbeds and boiling away its oceans, the planet took on the characteristics of a desert ecosystem. Whereas when Luke is on the planet Hoth that’s more of an Arctic Tundra situation.

These miniature versions of ecosystems can teach budding naturalists a lot about the real world, even if what’s in the mason jar is from Middle-earth or Narnia. Or elsewhere …