Enclosed terrarium: which plants to choose?

Tired of your kitten nibbling on the leaves of your poor little plant? Instead of turning the poor feline into a bonsai cat, keep your plants in a sealed terrarium. In addition to being decorative, these airtight jars let you grow demanding plant species with almost no effort—as long as you choose the right varieties.

Upright baby plants to add height to your terrarium

Add decorative elements to create ambiance – Photo by Clayton Leite / Pexels

Your terrarium needsan upright plant to add height and dimension to your arrangement. It helps you make the most of the available space in your jar and draws the eye.

Ferns thrive in humid environments. They're perfect plants for your terrarium. Depending on your tastes and your project, choose the wavy fronds of the bird's nest fern, the lacy foliage of boston Fern (Nephrolepis exaltata), or the vibrant green of Phlebodium aureum (Phlebodium aureum). Your ferns will thrive in their glass home. They'll grow faster than they would outdoors. Buy small specimens and prepare a container tall enough to accommodate them.

Do you prefer mini-terrariums? Choose tropical plants. They'll grow more slowly, and you can prune them to control their growth. Calathea adapts well to indoor cultivation. Look for varieties with a slender habit and narrow leaves, such as goeppertia lancifolia or goeppertia warscewiczii. The Begonia maculata and syngonium wendlandii also work well in a jar. Their leaves fill the space without overwhelming it.

If you want to give your terrarium the look of a Japanese garden, check out the asparagus plants. With its dark green foliage and umbrella-like silhouette, asparagus setaceus (Asparagus setaceus) looks like it came straight out of the sets of Princess Mononoke. As for asparagus sprengeri (Asparagus aethiopicus), it could provide a home for Totoro to take a spring nap.

Some orchids require at least 70% humidity and are difficult to keep alive in an apartment. But in a terrarium, caring for these delicate plants is a breeze. The large green and gold leaves of the Macodes petola “jewel orchid” will look stunning in a demijohn. And you won't have to do a thing to care for them.

Bonsai for a decorative touch

In a jar, bonsai look giant – Photo by Qnula / Canva

You can also add some vertical interest by planting small shrubs. Saw Palmetto (Chamaedorea elegans) grows very slowly and thrives in humid environments. These two characteristics make it a nightmare as a houseplant, but an ideal candidate for growing in a closed terrarium. For a modest price (about six euros), you can get a plant just a few centimeters tall. With its drooping fronds, your miniature palm will give your creation the feel of a paradise beach.

Do you dream of a tropical jungle? Coffea arabica
(Coffea arabica) will transform your candy jar into the Amazon rainforest—minus the tarantulas and snakes. This bushy plant thrives in high humidity and can flourish beautifully in a terrarium.

Less common, the Aralia (Polyscias fruticosa) can also be grown in a confined space. This shrub, with its gnarled trunk and lobed leaves, grows quickly when exposed to full sun. To slow its growth, place your terrarium in partial shade.

Finally, if you're worried about killing your plants—even in a terrarium— schefflera arboricola can put your mind at ease. The umbrella tree is hardy, even when young. Sunny exposure is recommended, but it can tolerate partial shade.

Epiphytic plants to prevent soil from sticking to the terrarium walls

Tillandsia thrives in the terrarium's humidity – Photo by Sonny Abesamis / Flickr

Epiphytic plants have no roots. They don't need soil to grow and can cling to just about anything. In a closed terrarium, this unique trait lets you create the wildest arrangements. Branches, seashells, pebbles, other plants… It's up to you to provide the support that inspires you.

Air plants (Tillandsia) are native to the Americas. They're among the easiest epiphytes to care for in a terrarium. Indoors, it's best to perform several rounds of misting a day. But in a jar, you hardly have to do anything.

Creeping plants to cover the ground

Fittonia and Hypoestes add color – Photo by Jans Martino

Creeping plants are another essential element of your terrarium. To make them look spectacular, focus on the color and shape of the leaves.

Fittonia albivenis comes in almost every shade imaginable. Its green, pink, white, or red foliage is accented by a dark central vein. You can play with contrasts by pairing a pink Fittonia with an Asparagus, or create a monochromatic look by placing a plant with lime-green leaves next to a fern. Fittonia albivenis will thrive in a closed terrarium. It will grow quickly, so you'll likely need to prune it.

The freckled plant (Hypoestes phyllostachya) offers a wide variety of colors. You can use it to highlight the rest of your terrarium or give it its own jar to showcase the patterns on its foliage. When potted indoors, this species is always thirsty. But in a closed environment, it benefits from condensation, so you don't have to water it too often.

With its green and white leaves, ficus pumila (Ficus pumila) is a more traditional alternative. However, the plant is just as effective at forming a carpet of greenery in your terrarium. The icing on the cake is that this ficus is hardy. It's not likely to lose its leaves during the first few days of the acclimation period.

Finally, if you're planning to create a romantic garden atmosphere in your terrarium, try Common ivy (Hedera helix). You can pair it, for example, with a fern to create an English woodland effect. Like the other groundcover plants on this list, this vine is hardy. It requires very little care, especially in a closed jar.

Mosses to Play the Role of Spies

Green and dense, these mosses look healthy – Photo by Lucy Serafi / Wikipedia

An essential decorative element in closed terrariums, mosses also provide information about humidity levels and the condition of the substrate. As long as they stay green, everything is fine. But if they start to turn yellow, it means your terrarium is lacking water. It's then time to water it, preferably with rainwater. But which moss should you choose? It depends on your personal taste and the plants you've already selected.

Ball moss (Leucobryum glaucum) is appealing for its round shape and bright green color. It's an excellent choice if you've planned to include plants that thrive in partial shade or if you want to place your terrarium in a spot with soft, filtered light.

Marchantiophyta sp. has a more irregular shape. It can hug the contours of a rock, a root, or any other raised feature you want to highlight (or conceal). Once well-established in the terrarium, this bright green moss requires no special care.

Selaginella kraussiana may be a primitive plant, but its foliage is no less intricate. The leaves—bright green, light green, or acid green—are deeply lobed. They add a graphic touch to a minimalist arrangement. As for care, there's nothing to worry about. Selaginella thrives in the humidity and constant temperature of the terrarium. You'll need to remove any yellowed leaves that appear after a few years, though.

Plants to Avoid in Your Closed Terrarium

For your succulents, opt instead for an open, dry terrarium – Photo by Urban Botaniste / Flickr

When setting up your closed terrarium (or purchasing a kit from a store), make sure all the plants have the same requirements in terms of substrate, light, and temperature. Check the care guides on the Monstera app. We'll tell you the recommended exposure and soil type. Never mix a variety that requires bright light with a species that can't tolerate direct sunlight—even if the result looks charming.

Also make sure that life inside a sealed jar is suitable for your plant. The closed terrarium method is best for plants that thrive in humidity, such as tropical varieties and ferns. But be careful! It's not recommended for plants native to arid environments, such as cacti and succulents. House leeks, Echeveria, and sea urchin cacti, on the other hand, are perfect for a living wall or an open terrarium. Other plants, classified as semi-succulents—such as chinese money plant and Peperomia—will not thrive in this environment either. They will survive, but excessively high humidity may cause their leaves to become limp and droopy.

Carnivorous plants, such as dionaea muscipula), Nepenthes, and sundews (Drosera), can be grown in enclosed environments. However, their growing conditions are specific (watering exclusively with rainwater and acidic potting mix) and are rarely found among the varieties typically planted in enclosed containers. It's best to dedicate a separate terrarium to them and not mix them with plants that have different needs.

Experienced gardeners also recommend avoiding fast-growing plants, such as pothos or monstera deliciosa. Mini cuttings will look very pretty in a terrarium. But after a few months, they'll start touching the walls. You'll need to either prune them or repot them into a larger container.

Finally, steer clear of fragile plants that have a hard time adapting to change. They may not survive the first few days while the terrarium regulates its humidity. It would be a shame to ruin your creation with a half-dead Alocasia or a sparse Ficus microcarpa.

Have you just bought your first terrarium and aren't sure what to do? Check out our Nine tips for maintaining your closed terrarium on the blog.

Frequently Asked Questions About Plants and Closed Terrariums

What plants should you put in a closed terrarium?

Plants suitable for a closed terrarium are generally tropical species that thrive in humidity and heat but tolerate limited space, such as ferns, Fittonia (mosaic plant), and Marantaceae. You should also add mosses to maintain the balance in your terrarium.

How do you care for plants in a closed terrarium?

Since water circulates in a closed loop, watering is very limited in a terrarium. A light watering, two to three times a year, is usually sufficient. However, you should open the lid several times a month to prevent excessive condensation and mold growth. Finally, remember to prune plants that have grown too large and remove dead leaves.

Can you combine several types of plants in a closed terrarium?

Yes, but you should choose plants with similar needs for humidity, light, and temperature. For example, you can combine plants that prefer partial shade, such as Marantaceae and ferns. The goal is to create a harmonious ecosystem.