The Remarkable Longevity of a Closed Terrarium with No Additional Water

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Lawn & Garden

In 1960, David Latimer, an electrical engineer from Surrey, England, created a closed bottle garden similar to this one. A closed terrarium is a self-sufficient ecosystem that has everything it needs to survive. Lucy Serafi/Wikimedia Commons (CC By-SA 4.0)

On Easter Sunday in 1960, David Latimer cleaned out a 10-gallon (38-liter) glass carboy that had previously contained sulphuric acid. He filled it with compost, planted a single spiderwort seedling at the bottom, added a little water, and corked it. Latimer then placed it under a stairwell in his home where it received indirect sunlight and rotated it periodically to ensure even growth.

For over 60 years, Latimer’s closed terrarium has thrived with very little intervention. It is a wholly self-sufficient ecosystem. Only once has the carboy been opened — in 1972, when he added a little water. The terrarium serves as a simplified model of how life on our planet can sustain itself — as long as it receives all the necessary sunlight.

A closed terrarium, like Latimer’s, operates by replicating three fundamental cycles found on Earth: the water cycle, the oxygen cycle, and the nutrient cycle.

Firstly, the terrarium has its own water cycle: since no water is lost, the same water molecules circulate endlessly in the container. The water gets absorbed by the plant’s roots, is transpired through the leaves, condenses on the sides of the container, and flows back down the sides into the soil.

The plant’s survival is supported in the same way as all plants in ecosystems throughout the world. Aerobic bacteria in the compost decompose the dead plant matter, creating more nutrient-rich soil for the plant to use. The bacteria also consume the oxygen released by the plant, converting it into carbon dioxide, which is necessary for the plant to undergo photosynthesis.

Latimer had no intention of creating the world’s oldest terrarium. He didn’t even mention it to anyone until he brought photos to a BBC gardener’s question show to ask if his experiment would be of interest to experts. Latimer plans to pass the terrarium on to his children or leave it to the Royal Horticultural Society.

Now That’s Interesting

Although Latimer’s bottle does not contain insects, some closed terrariums can support populations of insects or snails.


1. What is a closed terrarium?

A closed terrarium is a miniature ecosystem made up of plants, soil, and rocks enclosed in a clear container, typically made of glass or plastic. The container is sealed, creating a self-sustaining environment where water is recycled and the plants maintain their own oxygen levels.

2. How does a closed terrarium survive without water added?

A closed terrarium survives without water added because it is a self-contained ecosystem. The plants inside the terrarium release moisture through transpiration, which condenses on the walls of the container and falls back to the soil. The water is then absorbed by the roots of the plants and the cycle continues. This process is known as the water cycle, and it allows the terrarium to maintain a stable environment without the need for additional watering.

3. What plants are best suited for a closed terrarium?

Plants that are best suited for a closed terrarium are those that thrive in high humidity and low light environments. Some popular choices include ferns, mosses, air plants, and certain types of succulents. It is important to choose plants that are compatible with each other and the size of the container, as they will need to coexist in the same environment for an extended period of time.

4. How often should a closed terrarium be opened?

A closed terrarium should only be opened if there is excess moisture or condensation on the walls of the container. If this occurs, the lid can be removed briefly to allow for ventilation and to prevent the plants from becoming too moist. However, opening the terrarium too often can disrupt the delicate balance of the ecosystem and should be avoided.

5. Can a closed terrarium be placed in direct sunlight?

A closed terrarium should not be placed in direct sunlight, as this can cause the temperature inside the container to rise and create an inhospitable environment for the plants. Instead, it should be kept in a location with indirect light, such as a north-facing window or under a fluorescent light.

6. How long can a closed terrarium live for?

A closed terrarium can live for decades if properly cared for. The plants inside the container will grow and evolve over time, creating a unique and beautiful micro-landscape that can be enjoyed for many years. Regular monitoring and maintenance, such as pruning and removing dead foliage, can help to ensure the longevity of the terrarium.

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