Need Something to Do? Here's How to Make a Terrarium in 5 Simple Steps

For those of us who dream about a lush, green garden but don't have the space, a terrarium can be a pretty decent alternative. Plus, whether you have a green thumb or you can't keep a plant alive to save your life, most terrariums are fairly easy to maintain and they thrive pretty well without a lot of effort.

A terrarium is a great project if you have a little bit of time (say, 2-3 hours depending on the extensiveness of your design) and want to create a thriving little habitat fit for any coffee table.

Supplies for Making a Terrarium

Here’s what you need to get started:

• A glass container (must have an opening large enough to fit a plan inside)
• Small stones, gravel, or a similar material for a base
• Potting charcoal
• Soil
• Plants
• Chopsticks or tweezers
• Decorative elements (optional)
• A small trowel
• Spray bottle (optional)

Choose Your Plants

Before you get started creating your terrarium, make sure you’re using plants that will thrive in their new environment. First, you’ll need to check that they can even fit inside the vessel you’ve selected. But just as importantly, you’ll want to select plants that do well in humid conditions. Some popular ones used in terrariums include Tillandsia stricta (commonly known as air plants), Watermelon Peperomia, and Starfish Flower Cactus.

A quick word on using succulents: While they can do well in terrariums, their natural environment is extremely dry. To compensate for the high humidity levels, make sure your vessel is relatively shallow and has several openings, allowing your succulents to fully dry out between waterings.

Choose Your Container

Your next step is to decide on the type of container you’d like to use for your terrarium. There are countless options out there, from simple jars and bowls to stylish geometric designs. Don’t be afraid to repurpose around-the-house items, like Mason jars.

The main thing you’ll need to pay attention to is whether your container is open or closed. Closed setups are essentially self-sufficient, with the plants inside feeding off the trapped moisture in the air. Open ones require a bit more maintenance, and are better suited to plants requiring dry conditions and good airflow.

Build Your Layers

To start, add a thin layer of stones to the bottom of your container (aim for around 1.5 inches). This will help provide drainage for your plants. Next, add a layer of activated charcoal—keep it on the thin side. This is your terrarium’s filtration system, keeping your plants’ water fresh and preventing bacterial growth. 

For the third layer, place some potting soil on top of the activated charcoal. Most types will work, but if you’re working with succulents and cacti you’ll want to stick with a soil type intended for those types of plants. As you build this layer, be sure to add enough soil to accommodate your plant’s roots (you can even form a hole as you work). The soil layer should be thicker than the previous two, with all three adding up to around a third of your terrarium’s height. Make sure it’s well-packed and free of air pockets.

Add Your Plants

Now it’s time for the most important step: putting your plants inside the terrarium. Once you’ve taken them out of their containers, brush any excess soil off of the roots. Place your largest plants inside the terrarium first, working your way down to the smallest in order of size—use your tweezers or a set of chopsticks to get those tiny plants placed just so. These tools are also helpful if your vessel has a long, narrow opening. 

Set each plant into the holes you’ve formed in the soil and lightly pack them in place (don’t overcrowd). With your plants set, all that’s left is to add any extra features or decorations to complete your mini garden-scape.

Follow a Maintenance Routine

If you have a closed terrarium, give it a daily spritz with a spray bottle. For open ones, water once a week—aim for damp or slightly moist soil, not completely saturated. Due to their humid environment, closed terrariums should rarely (if ever) need anything beyond that daily misting.

As your plants grow, you may find that you need to prune them back from time to time. Don’t put this off indefinitely—removing dead growth can prevent rotting and keep your plants (and terrarium) looking vibrant for a long time to come.