How Long Do Closed Terrariums Last?

Terrariums, also referred to as glass gardens, are a way to get creative, design, and construct miniature ecosystems of small plants and decorative items within a glass enclosure/box/case.

Terrariums, when properly constructed and cared for, can bring elements of nature into your home or workspace. Closed terrariums should require less attention and maintenance overall than other household plants.

In fact, under the right conditions, a well-balanced closed terrarium should last forever.

When your terrarium is balanced, you should see some condensation forming at the top of the jar – if there is no condensation, then the glass should be crystal clear.

A terrarium can last a long time without any interruption of care and even longer with some periodic care. In addition, just because it is a closed terrarium does not mean that it can never be opened to perform the necessary care from time to time.

How Long Do Closed Terrariums Last?

Open Bottle Terrarium

If you take good care of terrariums, they can live a lot longer than you think.

Sure, they are nice at first, but the wrong plant choices or setup will be like a bomb counting down.

Others simply will not do well under those conditions.

If you keep them closed, and seal outside humidity you can keep your nutrients and fresh water in for long time.

In theory, a perfectly balanced closed terrarium should outlive all of us!

There are so many houseplants that die because of too many environmental issues.

Definitely the best thing to happen is to have no less than 1/2 of water in the container, but more is better.

Anything water left in the terrarium will eventually drone and rancid, and could cause roots to mold.

Also make sure that your plants are getting the right amount of light. A decent rule is one hour before sunrise and one hour after sunset. It could always be worse to over-fertilize.

That ever-so-slightly can and will cause algae growth, and deteriorate plant roots that are growing in your terrarium if you fertilize too often.

If you live in an area with snow, it is best to cover your closed terrarium with a lid so that the moisture does not have the opportunity to get inside your terrarium.

And lastly: The seasons play apart in the plant’s growth. For example, in the winter, you may find that your plants may need the water (temperature) more than normal, and may even grow slower.

What Affects The Lifespan Of A Closed Terrarium?

Closed terrarium lifespan 1

If you plan to keep the terrarium for over two years, or intend on leaving the plants outside year-round, be sure to monitor them.

Closed terrariums need regular observation to ensure a healthy environment for the plants.

To help your closed terrarium last longer, be careful to avoid the following mistakes.

Excessive Lighting

Most plants that are suitable for growing in a terrarium do not need much light either.

Additionally, the glass of the terrarium may also act as a magnifying lens, intensifying sunlight, which can damage your plants by burning them.

The heat inside a terrarium can escalate very quickly making it an increasingly humid environment, and before long, your terrarium may be as humid as a sauna.

Recommended is to place terrariums, if possible, away from direct sunlight because, again, most plants cannot deal with excess heat.

Inadequate Lighting

Although excessive light can be harmful, most plants need some light to sustain themselves.

If your terrarium is not getting enough indirect light, try supplementing with grow lights, or fluorescent lighting; or moving it closer to a window that has sufficient but indirect light.

Excessive Proximity to Heat Sources

Radiator heat or that from a heating vent can quickly kill or destroy your plants.

IMPORTANT: Most terrarium plants will die if you place them on a radiator, or even near an active heater!

Overgrown Plants

Trim your terrarium plants if they become overgrown and overcrowded in the terrarium.

You might also want to trim back the roots to keep them small.

You want to be able to appreciate the individual plant and be able to see the other ornamental aspects inside the terrarium.

Refusal to Remove Dying Plants

Terrarium cleaning

If you see that a plant in your terrarium seems sick or dead, or just not doing well, remove it right away, as it may infect any other plants in your terrarium.

Using a small shovel, chopsticks, terrarium tools, or a spoon, remove the plant, and be careful not to break the roots of any other plants.

Replace the plant with a same size and similarity of light and moisture needs.

Carefully place the new plant in the soil, making sure it is surrounded, and in good contact with its soil, leaving no pockets of air.

Selecting the Wrong Plants

Though nearly anything can be grown in a terrarium, it is important to select plants that will thrive in the type of terrarium that you are making.

If you are making a closed terrarium, choose plants that can live in the wetness. And as with any gardening, mix plants that have an identical requirement for light.

Best: Low-light plants are typically better.

What Plants Are Fit to Grow in A Closed Terrarium?

Mini African violets

The plants that are selected for use in a terrarium can impact the level of ease in taking care of the terrarium, as well as the longevity of the plants itself in a terrarium per se. 

It is not necessary to use a variety of plant species to create an interesting little ecosystem. It’s important to use plants that have similar general environmental preferences. 

Needs for light as well as moisture and temperature preferences are some standard environmental parameters. It is also always nice if those plants are on a similar pattern of dormancy. 

You do not want to include a plant that gets too large or grows too fast. Pruning helps only to a point, and then replanting the Area you have chosen for these aggressive grower can become tiresome.
 
Even with limited trimmings, you may also find you have plants that will take over the space without any regular care in any form. 

Mosses and ferns are particularly appealing when found in a terrarium, not to mention stylish plants like Baby Tears, Peperomias, and Pilea can be much easier to grow under glass than a dry windowsill. 

Low growing nerve plant and exotic epiphytes are other selections. 

Mini African violets, small orchids, and other odd flowering exotics also thrive in a terrarium situation and add color to the environment around them.

Final Thoughts

Usually, Closed terrarium gardens use clear containers, either made of plastic or glass.

They are sometimes even lined out with cardboard. Under the right conditions, an established, healthy, closed terrarium can not just survive, but last almost indefinitely.

The overall job is to monitor moisture levels in the system, and to change the moisture level whenever necessary. You will need to routinely check on pruning, transplanting, cleaning the glass, occasional fertilizing, and removing mildew and dead material.

All of these task which are reasonably required, contribute to the longevity of the closed terrarium.

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