Welcome to the enchanting world of terrariums – miniature gardens nestled within glass containers, creating their own self-sustaining ecosystems.
Terrariums can range from lush rainforest environments, complete with ferns and mosses, to arid desert landscapes adorned with hardy succulents.
Welcome to “The Ultimate Guide to Terrariums”, your comprehensive roadmap to navigating the enchanting world of these tiny tabletop gardens.
In this guide, we will delve deep into the fascinating realm of terrariums, covering everything from their history to their many diverse forms.
We’ll explore the science that makes them work, the plants that thrive in them, and the aesthetic pleasure they can bring to any space.
This guide also provides practical, step-by-step instructions on how to create your own terrarium, plus troubleshooting tips to ensure your miniature ecosystem flourishes.
So, whether you’re a first-timer looking to start your journey or an experienced terrarium enthusiast seeking to broaden your knowledge, this guide is designed to equip you with all you need.
The brief history of terrariums

The history of terrariums dates back to Victorian England and is attributed to Dr. Nathaniel Bagshaw Ward, a London physician and botanist.
In 1827, Ward unintentionally discovered that plants could survive in a sealed glass jar, creating a self-sustaining ecosystem.
The sun warmed the air inside, causing a natural water cycle through evaporation and condensation, essentially a mini-greenhouse.

Dr. Nathaniel Bagshaw Ward (1791 – 4 June 1868 in St Leonard’s, Sussex)
Realizing the potential, Dr. Ward developed the first “Wardian case,” a sealed glass and wood container that was instrumental in transporting plants over long distances during the British Empire’s expansion.
This ability to safely transport plants revolutionized horticulture.
Today, these cases have evolved into the decorative terrariums we know, loved for their aesthetic appeal and the fascinating glimpse they offer into plant life and ecosystems.
Just so we’re clear, what is a terrarium?
A terrarium is essentially a miniature, self-sustaining ecosystem housed within a clear container, usually made of glass or plastic.
These containers provide the perfect environment for small plants to thrive, replicating the natural growing conditions by creating a humid, enclosed space where water can cycle in a manner similar to the earth’s natural water cycle.
From lush forests to arid deserts, a variety of landscapes can be replicated in terrariums, each hosting its unique set of plants.

The benefits of creating a terrarium
Having a terrarium offers multiple benefits, beyond their obvious aesthetic appeal.
Educational Value: Terrariums provide a fascinating peek into how ecosystems work, making them a great educational tool for both children and adults. They demonstrate processes like photosynthesis, respiration, and the water cycle in action.
Therapeutic Effects: The process of creating and caring for a terrarium can be therapeutic. It can act as a form of ‘green therapy’, reducing stress and promoting a sense of calm.
Low Maintenance: Once established, terrariums require minimal care, needing only occasional watering and pruning. This makes them perfect for individuals with a busy lifestyle or those new to gardening.
Space-Efficient: Terrariums, with their compact size, are ideal for adding a touch of greenery to small spaces like apartments, offices, or dorm rooms.
Types of terrariums
Terrariums can primarily be categorized into two types: closed and open.

Closed Terrariums: These are sealed containers that create a high-humidity environment. The enclosed space creates a self-sustaining water cycle; moisture from the soil and plants evaporates, condenses on the walls of the container, and then falls back, mimicking rainfall. This type of terrarium is ideal for humidity-loving plants such as ferns, mosses, and certain tropical species.
Open Terrariums: As the name suggests, these terrariums are not sealed. They offer more air circulation and less humidity, creating a more arid environment. Open terrariums are well-suited for plants like succulents and cacti, which prefer drier conditions.
The different types of terrarium containers

Jars: Mason jars or apothecary jars are popular choices due to their wide openings and range of sizes. They’re also readily available and relatively inexpensive.
Vases: Glass vases, particularly those with unique shapes, can make for visually appealing terrariums. Ensure the opening is wide enough for planting.
Fish Tanks: Fish tanks or aquariums, especially the small ‘betta fish’ tanks, can make excellent large terrariums, offering plenty of space for a variety of plants.
Cloches: These are glass, originally designed to protect outdoor plants from cold temperatures. They make elegant, dome-shaped terrariums.
The characteristics of a good terrarium container
Transparency: Terrarium containers should be transparent to allow sufficient light for the plants. Glass or clear plastic are the best materials for this purpose.
Size: The size of the container will dictate the amount and types of plants you can include. Larger containers can accommodate a greater variety of plants, while smaller ones are best suited to one or two types.
Access: The container should have an opening wide enough to allow for easy placement and arrangement of plants and materials. This is especially important for closed terrariums, as you’ll need to reach inside to care for your plants.

Tips for choosing the right container
Consider Your Plants: Think about the types and sizes of plants you plan to include. Different plants require different conditions, so choose a container that will best support your chosen plants’ needs.
Think About Placement: Where you plan to display your terrarium can also influence the choice of container. If you have a specific spot in mind, consider the available space and lighting conditions.
Easy Maintenance: Choose a container that allows for easy maintenance. A container with a wider opening will be much easier to work with, especially when you need to trim or prune your plants.
By keeping the needs of your plants and the aesthetics of your space in mind, you can find the perfect home for your miniature ecosystem.
Selecting suitable plants for your terrarium
Just like a painter choosing the right colors for a canvas, selecting the right plants for your terrarium requires careful consideration.
The plants you choose will set the tone and character of your miniature ecosystem.
Factors to consider
Light Requirements: Different plants have different light needs. Some thrive in bright, indirect light, while others prefer low light conditions. Always match the plant to the lighting conditions of the space where you plan to keep your terrarium.
Humidity: Some plants love humidity, while others prefer drier conditions. Closed terrariums generally create a humid environment, whereas open terrariums are less humid.
Size: Terrarium plants should be small enough to fit comfortably in your chosen container. Also, consider their growth habits. Some plants grow taller, while others spread out.
Compatibility: If you plan to use multiple plants, make sure they have similar needs in terms of light, water, and humidity. This will ensure all plants thrive in the same environment.
Suitable plants for closed terrariums

Closed terrariums create a humid environment and are ideal for moisture-loving plants.
Ferns: Small ferns like maidenhair fern or button fern are great choices due to their love of moisture and their delicate texture.
Mosses: Mosses, such as sheet moss or cushion moss, work well in closed terrariums. They can cover the soil and create a lush, verdant look.
Fittonia (Nerve Plant): Fittonia plants have beautiful, colorful foliage and thrive in the humid environment of closed terrariums.
Peperomia: With their compact size and attractive leaves, various Peperomia species, such as Peperomia obtusifolia and Peperomia caperata, make excellent choices for closed terrariums.
Pilea (Moon Valley): Pilea plants have textured leaves that create an interesting visual appeal in closed terrariums.
Suitable plants for open terrariums

Open terrariums offer more airflow and less humidity, making them suitable for plants that prefer drier conditions.
Succulents: Plants like echeveria, haworthia, or sedum are perfect for open terrariums due to their low water needs.
Cacti: Small cacti can add an interesting visual element to your terrarium. Just be careful when handling them!
Air Plants: Air plants that thrive in lower humidity can do well in open terrariums. They don’t require soil, which adds a unique aesthetic.
Where to source your plants
Your local garden center or nursery is an excellent place to start your search for terrarium plants. They often have a variety of small plants suitable for terrariums.
For a wider variety, online plant retailers can offer rare and unique species – just ensure that the plants are healthy and pest-free before introducing them into your terrarium.
Tools and materials needed to build a terrarium

Creating a terrarium is a bit like assembling a puzzle; each piece has a specific role to play in creating the final picture.
Here’s a list of essential tools and materials you’ll need and the role each one plays in the terrarium ecosystem.
Terrarium Container: This is the vessel that will house your mini ecosystem. It can be any transparent, glass or plastic container like a jar, vase, or fish tank.
Small Stones or Pebbles: The first layer in your terrarium, these facilitate drainage. Water trickles down through the soil and is trapped in this stone layer, preventing the roots from becoming waterlogged and rotting.
Activated Charcoal: This is often used in aquarium filters and has excellent absorption properties. A thin layer of activated charcoal helps keep the water fresh and prevents mold and bacteria growth.
Potting Soil or Compost: This will be the main growing medium for your plants. It should be light and well-draining. For succulents and cacti, a special cacti/succulent mix is recommended as it provides the excellent drainage these plants require.
Plants: Choose plants that are suitable for the type of terrarium you’re creating (closed or open) and that will thrive in the location where you plan to keep the terrarium.
Decorative Items: These can include anything from small figurines to shells, crystals, or decorative rocks. These items can add a touch of personality to your terrarium.
Tools: Some basic tools can make the assembly process much easier. These can include:
- Long Tweezers or Tongs: These can help with placing plants and materials, especially in deeper containers or hard-to-reach areas.
- A Spoon or Small Shovel: This is useful for adding and spreading soil.
- A Spray Bottle: This helps to water your plants with a gentle mist, preventing overwatering.
- A Brush: A small brush can help clean the interior walls of the terrarium, keeping the view into your miniature world clear.

Building Your Terrarium: A Step-by-Step Guide
Building your terrarium is a rewarding and artistic process. By following these steps, you can create a miniature world that will thrive and bring a touch of nature into your space.
Step 1: Cleaning/Preparing the Container
Start with a clean container to prevent any unwanted bacteria or fungi from affecting your terrarium. Wash the container with warm soapy water, rinse thoroughly, and dry before you start. If your container has a narrow neck, a bottle brush can be useful for cleaning inside.
Step 2: Creating the Drainage Layer

The first layer in your terrarium is the drainage layer. Add a layer of small stones or pebbles to the bottom of your container. The thickness of the layer depends on the size of your container, but aim for around 1-2 inches. This layer ensures that excess water can drain away from the plant roots, preventing waterlogging.
Step 3: Adding Activated Charcoal
Next, add a layer of activated charcoal over the stones. The charcoal helps to keep the water fresh and prevent the buildup of bacteria and mold in your terrarium. This layer doesn’t need to be thick; a light covering of charcoal is sufficient.
Step 4: Adding the Soil
Now, it’s time to add the soil. The type of soil will depend on the plants you’re using. For most plants, a good quality potting compost will be fine, but if you’re using succulents or cacti, use a special cacti/succulent mix. The soil layer should be deep enough for your plants’ roots to spread; 2-3 inches is usually enough.
Step 5: Planting Your Flora
Before you plant your flora, it’s a good idea to plan out your arrangement. Once you’re happy with your design, dig small holes in the soil and gently place your plants in them, being careful not to damage the roots. Use a spoon or tweezers to help position the plants. Once planted, gently press the soil around the base of each plant to secure it.
Step 6: Adding Decorative Elements
This step is where you can let your creativity shine. Add any decorative elements you like, such as figurines, shells, or crystals. These should complement your plants and not overwhelm them. Remember, the plants are the stars of the show.

Terrarium care and maintenance
Congratulations! You’ve created a beautiful terrarium. But the journey doesn’t end here.
Proper care and maintenance are essential to keep your miniature ecosystem thriving.
Watering requirements

Closed Terrariums: The beauty of a closed terrarium is its self-sustaining nature. It creates its own water cycle. Water from the soil and plants evaporates, condenses on the walls of the container, and then trickles back down into the soil. Therefore, closed terrariums rarely need watering. However, if you notice the soil looks completely dry or plants start to wilt, a light misting will help.
Open Terrariums: Open terrariums, especially those housing succulents and cacti, require minimal watering. Overwatering can cause root rot and kill your plants. Water sparingly, only when the soil is completely dry.
Light requirements
Terrariums generally do well in indirect light. Direct sunlight can overheat your terrarium and burn the plants.
A north or east-facing windowsill is often an ideal location. However, if natural light is limited, artificial light like a fluorescent bulb or grow light can also work.
The key is to provide consistent light without overheating your mini ecosystem.
Temperature and humidity control
Most terrarium plants thrive in a temperature range of 65-75 degrees Fahrenheit.
Avoid placing your terrarium near heat sources like radiators or cold drafts from air conditioners.
As for humidity, closed terrariums naturally provide a high-humidity environment.
Open terrariums, on the other hand, offer a dryer setting. Make sure you’ve chosen plants that suit the humidity conditions of your chosen terrarium style.
Pruning and managing plant growth
Regular pruning helps manage growth and maintain the aesthetic of your terrarium.
If plants become too large, they can be pruned back with a pair of small scissors or tweezers.
If a plant starts to rot or die, it’s essential to remove it promptly to prevent any disease from spreading to other plants.

Resolving common terrarium problems
Terrariums are generally hassle-free, but occasionally, you might encounter a few challenges. Let’s go through these common problems and provide clear actions for each to ensure your terrarium remains a thriving ecosystem.
Overwatering and underwatering
Overwatering: Symptoms include yellowing leaves, wilting, or an overly damp appearance. If this occurs, take the following steps:
For closed terrariums: Remove the lid for a couple of days to let some of the excess moisture evaporate.
For open terrariums: Cease watering and allow the soil to completely dry out before the next watering.
Underwatering: If your plants are shriveled or brown, they might be thirsty. Here’s what to do:
Lightly mist your plants with water and keep a close eye on them to ensure they start to recover.
Mold and algae growth
Mold and algae can occasionally appear due to the humid environment. If this happens, act as follows:
Remove small amounts of mold or algae with a clean cloth or cotton swab.
Increase airflow within your terrarium. In a closed system, consider leaving the lid off for a couple of hours each day.
Pests
While pests are uncommon in terrariums, they can occasionally appear. If tiny bugs are spotted:
Immediately remove the infested plant to prevent the pests from spreading.
Treat the affected plant separately using a diluted insecticidal soap, if necessary.
Plant diseases
Most plant diseases in terrariums are related to fungi or bacteria and are often tied to overwatering. If a plant appears unhealthy:
Remove the sick plant promptly to prevent the disease from spreading.
Ensure your tools are clean before and after working on your terrarium to prevent disease transmission.
Overcrowding
Overcrowding can lead to resource competition and increase the chances of disease. If your terrarium appears overly lush:
Engage in regular pruning to maintain the balance and aesthetics of your terrarium.
Remove any excess plants if necessary, ensuring each remaining plant has enough space to grow.
In conclusion…
The creation of terrariums is as exciting as it is challenging, however; armed with the right knowledge and know-how, you can create stunning self-contained environments.
We have written many more detailed articles on specific elements of terrarium, design, maintenance, creation and care – be sure to take a look and read up on any aspects you need to gain knowledge on.
If you are interested, we have listed 5 of the top external learning resources including books and courses below:
- Book: “The New Terrarium: Creating Beautiful Displays for Plants and Nature” by Tovah Martin: This book provides an excellent introduction to the art of terrarium making, with beautiful photographs and practical advice for both beginners and experienced gardeners.
- Book: “Terrarium Craft: Create 50 Magical, Miniature Worlds” by Amy Bryant Aiello & Kate Bryant: This book offers numerous unique and creative ideas for terrariums, along with step-by-step instructions.
- Podcast: “Epic Gardening Podcast” by Kevin Espiritu: While not exclusively about terrariums, this daily gardening podcast often dives into topics like indoor gardening and small-scale ecosystems, which include terrariums.
- Online Course: “The Terrarium Design School” on Udemy: This online course walks you through the process of designing and maintaining your own terrariums with video tutorials and expert advice.
- Blog: The Houseplant Guru: This blog by Lisa Eldred Steinkopf covers all things indoor gardening, including a range of articles on terrarium care and design.
Happy learning!