The 10 Best Plants for Your Open Terrarium (And the Worst!)
It can be daunting trying to understand terrariums and what plants work best for them, especially since this hobby can cost quite a lot. So to help you get started, here are the 10 best plants you can grow inside an open terrarium!
The 10 best plants to grow in open terrariums are:
- Air plants
- Aloe vera
- African violets
- Coleus
- Dwarf snake plants
- Good luck cacti
- Hens and chicks
- Lithops
- Peperomia hope
- Polka dot cacti
Not every plant will work inside an open terrarium, as you’ll discover later on. What’s great about this list is that you may already have some of these plants! After doing the work for you, here are the 10 best and most popular plants you can use to add to your collection.
1. Air Plants (Tillandsia ionantha)
Air plants thrive inside open terrariums and do not require much maintenance. To water them, simply remove them from the terrarium and submerge them in water before returning them inside the container.
Average Size: 2–4 inches (5–10 cm)
Growth Rate: Extremely slow
Watering Requirements: Moderate. Water whenever leaves curl inwards.
In an open terrarium with plenty of air circulation, air plants are a splendid choice. These fascinating plants can be light brown, green, or rosy pink.
As epiphytes, air plants survive in nature by hanging from trees and absorbing moisture through their leaves.
[quote] Air plants do not have any roots, making them excellent for soil-less terrariums.
Plus, they can be taken in and out of the container without any issues. Simply dunk them in water when their leaves curl and place them back inside to dry!
2. Aloe Vera (Aloe vera)
Aloe vera is an easy-growing succulent frequently seen in terrariums. This plant also has different varieties and species, making it easier to customize open terrariums.
Average Size: 3–6 inches (7–15 cm)
Growth Rate: Average
Watering Requirements: Low. Water when the soil is completely dry.
Desert-themed open terrariums require very little care, and the aloe vera plant fits perfectly in this environment.
With over 400 species and hybrids available in all kinds of sizes, patterns, and colors, you really can’t go wrong with growing aloe vera!
This reliable plant grows best in dry soil, so feel free to pair it with other cacti and succulents. But try to avoid growing them in nutrient-rich soil, as this could lead to the aloe vera outgrowing its companions after so many months.
Find out The 3 Best Pots for Aloe Vera outside of a terrarium!
3. African Violets (Saintpaulia ionantha)
The African violet is known for its beautiful and prolific blooms and can easily be grown in an open terrarium. Keep their leaves dry to help maintain their vibrancy.
Average Size: 3–6 inches (7–15 cm)
Growth Rate: Average
Watering Requirements: Moderate. Water every week.
African violets, or Saintpaulia ionantha, have been known as beginner-friendly houseplants for years due to their compact size and vibrant blooms.
In the right environment, you should be able to see it flower several times a year!
As if this wasn’t pretty enough, you can also find multiple cultivars with differently shaped leaves and flowers. The miniature versions will fit nicely in a small 6-inch terrarium.
The only downside I’ve discovered with these plants is that the leaves are prone to discoloration when damp. You’ll need to take extra care not to get their leaves wet during watering sessions, but I believe it’s worth persisting with.
4. Coleus (Coleus decurrens)
For a colorful terrarium plant, consider growing coleus. This attractive plant grows well inside open terrariums and will need to be pruned to stay small.
Average Size: 4–6 inches (10–15 cm)
Growth Rate: Average
Watering Requirements: Moderate. Water every 1–2 weeks.
When all the plants inside look the same, terrariums can quickly become dull monocultures. To help break up the monotony, consider using coleus.
Coleus is an easy-growing and colorful plant that you can use as a centerpiece inside your open terrariums.
Coleus grows pretty quickly when happy, so they’re better suited for larger terrariums. Alternatively, you can just use small cuttings or prune them regularly.
Since they require semi-frequent watering, these flashy plants should not be grown with succulents or cacti.
Discover more in the 20 Stunning Fast-Growing Indoor Plants for Your Collection!
5. Dwarf Snake Plants (Dracaena trifasciata)
Dwarf snake plants are excellent plants with slow growth rates that can live inside open terrariums. These plants are drought-tolerant and do not require much maintenance.
Average Size: 3–6 inches (7–15 cm)
Growth Rate: Extremely slow
Watering Requirements: Low. Water when the soil is completely dry.
As succulents, snake plants don’t need much water and can live in dry open terrariums. It can take them months or even years to generate new growth, so they’ll thrive inside a small container.
Some good examples would be the samurai dwarf, golden hahnii, or the bird’s nest snake plant.
Other snake plants like laurentii can also be used if you wish, although they’re better grown in larger terrariums or as a small leaf cutting.
6. Good Luck Cactus (Euphorbia trigona)
The good luck cactus, or African milk tree, is a unique succulent that thrives in open terrariums with little care. However, these plants must be handled with caution as they produce a toxic sap when cut. Keep them away from pets or children.
Average Size: 4–6 inches (10–15 cm)
Growth Rate: Slow
Watering Requirements: Low. Water when the soil is completely dry.
Unlike other low-growing terrarium plants, these succulents grow upwards and are great if you’re looking to add some vertical interest to your terrarium.
Given proper care, Euphorbia trigona plants can live inside a terrarium for years. Their roots like to stay dry and grow best in substrates with plenty of gravel and grit.
Just avoid touching any of its toxic sap. When cut, Euphorbia plants produce a milky irritating liquid as a defense mechanism, so be wary when handling cuttings!
Learn more in How to Propagate Good Luck Cactus (Your Final Guide!)
7. Hens and Chicks (Sempervivum tectorum)
Hens and chicks are beautiful and easy-to-care-for succulents that can be grown alone or with other terrarium plants. These plants prefer living in dry environments and do well in open terrariums.
Average Size: 3–8 inches (7–20 cm)
Growth Rate: Slow
Watering Requirements: Low. Water when the soil is completely dry.
If I could only choose to use one type of plant in an open terrarium, it’d be this one.
Because these adorable succulents have a habit of producing offsets as they grow, you can use a small pup to grow it with other plants or let them thrive and multiply in their own separate terrarium.
In several months, you’ll have an easy and attractive terrarium filled with matching hens and chicks.
I find that hens and chicks plants have long lifespans and are relatively hard to kill, making them ideal for beginners. They don’t need much water and are great for tropical terrariums or hot climates.
Learn more in How Often Do Hens and Chicks Need Water? (Your Final Guide!)
8. Lithops (Lithops)
Lithops require almost no attention and maintenance to live and can safely be grown in an open terrarium with little-to-no issues. However, they are highly sensitive to moisture and must be grown alone.
Average Size: 1–1.5 inches (2.5–3.8 cm)
Growth Rate: Extremely slow
Watering Requirements: Extremely low. Water only after it has fully split and the outer leaves have dried.
Lithops are commonly referred to as “living stones” and you’ll understand why when you realize how little attention these plants demand.
Depending on your lithops and its environment, you likely won’t need to water it for months, and it’ll still be quite happy.
Unfortunately, due to their sensitivity to water, these succulents are best grown alone.
Pro Tip: Give lithops at least 3 inches (7.62 cm) of gritty soil to accommodate for their roots.
Lithops rarely grow beyond the size of buttons, so you can keep up to 10 different lithops species in their own terrarium to make a fun decoration.
9. Peperomia Hope (Peperomia deppeana x quadrifolia)
Peperomia hope is a hybrid plant that will thrive inside airy, open terrariums. Keep these versatile plants out of direct sunlight and grow them in dry soils.
Average Size: 4–8 inches (10–20 cm)
Growth Rate: Slow
Watering Requirements: Low. Water when the leaves are wrinkled.
This is a simple but stunning plant. While peperomia hope is commonly grown as a regular houseplant, it’ll grow just as well inside a terrarium.
Peperomias have thick, circular leaves that stay small and look lovely against other typical terrarium plants.
Grown in an open terrarium, these gorgeous plants will have access to plenty of airflow. This is great and means they’re less likely to have their roots sit in water, which can wreak havoc.
They respond well to a variety of potting mediums and light, but they cannot handle direct sunlight, in particular. So be careful!
Learn How to Propagate Peperomia: 5 Effective Ways!
10. Polka Dot Cacti (Opuntia microdasys)
The polka dot cactus has a preferable slow-growing habit that is ideal for open terrariums. Only handle it with gloves to avoid making contact with their glochids.
Average Size: 6–12 inches (15–30 cm)
Growth Rate: Slow
Watering Requirements: Low. Water when the soil is completely dry.
I’ve only seen this in terrariums a handful of times, which is a shame because they’re quite attractive.
Their flat, paddle-shaped stems combined with their rabbit ear look to offer a unique feature for terrariums. Like many other cacti, opuntia is slow-growing and will maintain its small size for months.
The shallow root systems of Opuntia cacti allow them to grow in confined spaces with ease.
Learn more in our article, Do Cactus Roots Grow Deep? (The 3 Reasons Why They Don’t!)
To avoid touching their glochids or minuscule hairs, use thick gloves or tongs when handling this cactus.
The 3 Worst Plants to Grow in Open Terrariums
The 3 worst plants to grow inside open terrariums are 1) moss, 2) ferns, and 3) carnivorous plants.
Now we’re moving on from the best to the worst plants to use in open terrariums. The next species I discuss may be tempting, but they’re not ideal. Unlike closed terrariums, open terrariums do not have any lid or enclosure, so they cannot retain any moisture or humidity.
When you look at the best plants mentioned above, you’ll notice that many of them are drought-tolerant and can handle living in the dryness of an open terrarium. Let’s go over the 3 worst plants that cannot live in an open terrarium and the reasons why.
1. Moss
Moss plants require consistent moisture and humidity levels to thrive and cannot be grown in an open terrarium.
I’ve never seen a moss that I didn’t like. Nevertheless, these plants require damp settings with lots of humidity.
In an open terrarium, much of this needed humidity and moisture escapes through the opening, making it challenging to grow moss.
You could remedy this with daily misting. But this is a hassle to stay on top of, and it still may not be enough for the moss to acclimate and survive.
Additionally, it can be dangerous to grow moss in an open terrarium with other plants. Their watering needs are significantly different compared to the others, and you’ll likely overwater the surrounding plants.
If you like the look of moss, consider using this fake moss on Amazon to decorate your open terrariums without worry.
2. Ferns
Ferns grow best in regularly moist soils that may be too damp for other open terrarium plants to live. This plant will not thrive in a terrarium that is left open and must not be used.
Moisture is essential for keeping ferns alive. Left in an arid container, their tender foliage will quickly become dehydrated and wither away.
If you were to attempt growing ferns, you’ll likely see all the fronds dying and turning brown, an indicator that they’re suffering from low humidity.
These plants are also quite delicate and cannot handle direct sunlight. This makes them all the more unsuitable in an open terrarium, where many of the best plants are heat-loving succulents.
3. Carnivorous Plants
Carnivorous plants like Venus flytraps and nepenthes need constant moisture and humidity to survive. Therefore, they are unsuitable inside open terrariums, with too little water available.
You might argue that carnivorous plants come from tropical areas, so they should appreciate the airflow of an open terrarium, shouldn’t they?
This is true, but only to an extent. Many carnivorous plants like nepenthes fare from boggy wetlands and require much more humidity and moisture than an open terrarium can provide.
To stay healthy, nepenthes plants and Venus fly traps need at least 60% humidity to survive.
These exotic specimens may look attractive. But after a couple of weeks, they’ll most likely dry out and become yellow or black.
Unless you live in an area with high humidity, it’d be unrealistic to expect a carnivorous plant to live or flourish inside an open terrarium. So stick with the ones that are tried-and-true and you’ll have an easier time setting up your terrarium.
FAQs
What features make a plant best for open terrariums?
The most suitable plants for open terrariums are the ones that can tolerate drought and low humidity. Many succulents and cacti have these features, but other non-succulent plants, like African violets and coleus, can also be grown in terrariums.
How often do you water plants in an open terrarium?
How frequently open terrarium plants require water depends on the plants and the environment the terrarium is in. A succulent terrarium may only need water once or twice a month. A terrarium filled with moisture-seeking plants like coleus will need water every week.
Summary of Best and Worst Plants for Open Terrariums
The best plants to grow inside open terrariums are air plants, aloe vera, African violets, coleus, dwarf snake plants, good luck cacti, hens and chicks, lithops, peperomia hope, and polka dot cacti.
Conversely, the worst plants to use in open terrariums include moss, ferns, and carnivorous plants. These plants require generous moisture and humidity to flourish and cannot live inside an open terrarium.
Sources
- “Terrariums” by Mike Schnelle, David Hillock, Laura Payne in Oklahoma State University
- “African violets” by Julie Weisenhorn in University of Minnesota
- “Sempervivum tectorum” by n/a in NC State University
