As someone who has trouble keeping plants alive, I’m intrigued by terrariums. I think it’s because I also love miniatures (I have a “hobby” dollhouse I will finish someday when things slow down).  Terrariums are tiny creations that can serve as beautiful decorations AND teach about science and plants.  Win, win! They also provide something easy to care for that will last for a while (notice I’m not making a definite claim here, given my history).  It’s a fun, inexpensive, indoor activity for all ages (including Mom!).

First, a terrarium provides a creative outlet for a chilly fall day.  Gather your supplies first, based on the purpose of your project.  This may vary according to where the terrarium will be kept and who will be caring for it. 

• Will it be a centerpiece for Thanksgiving?  Choose a beautiful glass enclosure to fit your table. 
• Will your 4-year-old be responsible for it in his room?  Choose a plastic container with a lid!  Something transparent will do- the purpose is to both let in heat and light and confine the moisture. 

Remember the size of the hands that will be adding the materials.  You don’t want a glass bottle with a small opening because you won’t be able to fit your hand inside (think ship in a bottle). Include your kiddos in the planning and gathering.  It will spark their creativity and give them a sense of ownership to be involved in the trip to Hobby Lobby. 

Step-by-Step Guide to Building a Terrarium

Once you’ve chosen your container or containers, choose your plants.  Succulents work well in a terrarium because they don’t require much direct care.  Small houseplants and cacti will also work. Miniature ferns are a good addition if you’re looking for variety. Check the tags on the plants you choose to see about their maximum size.  Do they grow outward or upward?  You don’t want a short terrarium with a plant that grows up!  Maybe you even have some succulents at home that will work, saving you some money.  

Add rocks or pebbles to the bottle of your container to help the moisture in your terrarium drain. Your kids can find these outside, or you can purchase them at a store that sells aquarium supplies. There is usually a wide variety of colors and sizes, but again, keep the size of your overall terrarium in mind.   

Teaching Tip:  Have your kids research the difference between aquariums and terrariums.  

On top of the rocks, add a bit of sand to also filter water.  On top of the gravel, add a ¼ inch of activated charcoal.  Activated charcoal helps absorb odor and prevent bacteria growth, especially if your terrarium is closed. A thin layer of dried sheet moss is our next layer, keeping the soil separate from the drainage- it’s also pretty and gives another layer you can see from the outside.  Add an inch or two of potting soil on top of the sheet moss; this can vary based on the depth of your plants’ roots.

Once you’ve “layered,” you can carefully plant your plants. Ensure the plant’s roots are covered, and check to ensure your terrarium is visually appealing from the outside. Pay attention to where you place your plants; a short plant in the middle surrounded by taller plants might not allow you to see everything. Crowded plants might not be easy to see and care for. Depending on their ages, your kiddos can do much of this layering and planting themselves.

Teaching Tip: This is an excellent opportunity for students to look up other uses of activated charcoal.

Lastly, you can decorate your terrarium. Small shells, beautiful stones, tiny people or figurine animals can make it personal. Your kids might pick a Lego guy, a tiny beach ball, or even some battery-powered tiny lights to make it pretty. Adding live animals, like a turtle or a chameleon, would be fun, too, but it would increase the research required and the level of care involved.

Tips for Maintaining a Terrarium

Once you’ve created your terrarium, caring for it is simple! Add some water to the terrarium to get it started…after this, it will likely (depending on what plants you use) only require misting with a spray bottle.  A common mistake when caring for your terrarium is overwatering, so supervise this process if your kiddos are young.  Some closed terrariums only need misting every few months.  If moisture or water droplets form on your plants, it’s too wet.  If leaves wither and die, your terrarium needs a little misting.

Side Note: A closed terrarium is perfect for demonstrating the water cycle and may even “rain” inside!

Integrating with the Curriculum

The Mystery of Science curriculum provides a wealth of resources that align perfectly with projects like terrariums. Lessons can incorporate discussions on plant parts, soil health, and ecosystems. This hands-on activity serves as a springboard for deeper explorations into scientific concepts.

Educational Connections and Activities

If you don’t forget about it, your terrarium can last indefinitely!  Building a terrarium provides a hands-on learning experience that ties into science topics such as:

• Photosynthesis: Discuss how plants convert sunlight into energy.
• The Water Cycle: Observe how moisture condenses and recycles within the closed environment.
• Plant Biology: Examine different parts of the plant and their roles in survival.

Encourage your children to observe and note the changes they see in the terrarium over time. Integrate these observations into lessons or lab reports. This is a creative way for your students to “build” a science project that fosters responsibility in a low-stakes way. 

Bonus… it can decorate your Thanksgiving table!