So you want to build a terrarium

This hinged geometric terrarium is the go-to beginner vessel: the top opens wide for planting, the glass is thick enough to feel solid, and the proportions work: not so deep that tools can't reach, not so shallow that you can't fit a proper drainage layer. Start here and scale up once you know what style you want.

A gallon wide-mouth jar is the honest beginner's terrarium. It costs around $15, holds enough substrate for real plants, and the wide opening means you can plant with your hands instead of specialized tools. The lid creates a closed humid environment. Not the most photogenic build, but it teaches you all the same principles and costs nothing to experiment with.

A large glass terrarium box is the statement piece. The glass-and-metal frame sits on any shelf and reads as furniture. The swing lid opens fully (the best maintenance access you get in a glass container), and the proportions accommodate branching plants, taller mosses, and more ambitious hardscape. Buy this once you know what style of terrarium you're building.

Horticultural charcoal does two jobs: it absorbs toxins from decomposing plant matter, and it keeps anaerobic bacteria from colonizing your drainage layer. Most beginners skip it, then wonder why their terrarium smells like a swamp after a few months. It's cheap, it lasts forever, and it belongs in every terrarium whether open or closed, tropical or desert.

A good soil mix is the substrate everything above it depends on. Miracle-Gro Tropical is formulated for the moisture-retaining, nutrient-rich conditions that ferns, nerve plants, and tropical ground covers need. Swap it for a fast-draining cactus mix if you're building an open succulent terrarium. Don't use generic garden soil; it compacts and drains poorly in closed containers.

LECA (lightweight expanded clay aggregate) replaces your entire drainage layer with reusable clay balls that wick moisture without waterlogging roots. Popular in semi-hydroponic closed terrariums where you want to rewater from the bottom. More expensive upfront but reusable indefinitely, and makes root health much easier to monitor than gravel.

Fittonia is the textbook closed-terrarium plant: it's almost unkillable in a humid glass environment. The patterned leaves look dramatic in a small container, it stays compact, and it wilts visibly when it needs water, one of the few plants that communicates its needs clearly. Available at most grocery store floral departments and garden centers, or reliably via mail.

Air plants are the no-soil beginner option for open terrariums. They mount on rocks, shells, or driftwood without planting; just mist twice a week and soak in water for an hour every two weeks. Available in multipacks for under $20 and they teach terrarium design (composition, negative space, hardscape) without any of the layering complexity of a planted build.

An assorted succulent pack gets you hands-on experience with the most forgiving plant category available. Mix textures and rosette sizes in an open geometric container, variety reads as designed even when your compositional instincts are still developing. Fat Plants is a reliable Amazon seller with genuinely healthy plants, not the leggy, stressed specimens common in grocery stores.