The Terrarium You Bought From the Store Wasn't Made to Last – Here's How to Quickly Replenish It For a Longer Lifespan

Terrariums are some of the most charming additions to the indoor garden – that is, until they start to rot and fade away. But, with the right vessel and accompanying right plants you can actually keep a terrarium going for years on end. If yours is already looking a little worse for wear, here's how to quickly replenish it.

It's easy to make your own terrarium or you can purchase a pre-made one (like this beautiful terrarium kit from Amazon). However, if it contains plants that actually need more room than a terrarium offers, or they prefer drier or wetter conditions, it won't take long for it to all turn to brown mush.

Luckily, it's quite easy to replenish your terrarium. Here, I talk through what I do to refresh mine – trust me, it will last for years after this.

1. Choose the Right Vessel

One of the biggest terrarium mistakes I see with pre-made terrariums in is the wrong vessel being used.

There are closed and open terrariums, which are both fine to use but they determine what kind of plants they can hold.

Closed terrariums are much more humid environments and are better for moisture-loving plants, like fittonias and ferns. Open terrariums dry out more quickly, ideal for desert plants like cacti and some succulents.

However, if the vessel lacks good drainage and ventilation, it can harness an environment for rot and mold.

There should be a drainage layer and ideally a space for excess water to drain into. This is especially important for closed terrariums which don't have airflow and dry out more slowly.

Open terrariums that have narrow openings may also have limited ventilation and lack sufficient space for plants to grow.

You should also avoid any opaque terrariums or those with colored glass, as they can overheat easily and dehydrate plants.

Ultimately, (if needed) you should swap your terrarium for one that provides good drainage, airflow, and is easy to maintain.

This open glass terrarium on driftwood from Wayfair is my top pick.

2. Use Terrarium Soil

Terrariums with dense houseplant potting soil can hold onto excess moisture, leading to root rot and mold.

Instead, it's best to opt for specific terrarium potting mix (like this from Amazon) which is designed to have good drainage but also hold onto sufficient moisture to keep the plants hydrated.

Of course, if you're panning to make a succulent terrarium, you may want to use a sandy soil type. This succulent potting mix from Amazon is a good choice – I recommend pairing it with an open terrarium for desert plants, as they don't tend to enjoy higher humidity.

For extra drainage, add a layer of pebbles (like these from Walmart) at the bottom of the terrarium. This will prevent plant roots sitting in excess moisture.

3. Add Your Plants

There are so many terrarium plants to choose from but making the wrong choice for the type of terrarium you have can result in a premature decline.

Arid terrarium plants, like cacti and some succulents, do much better in open terrariums with good airflow. The high humidity of closed terrariums can result in mushy stems and dying succulents.

You can use this pack of mini succulents from Walmart to put your terrarium together.

Moisture-loving terrarium plants, like ferns and fittonias, are better suited to closed terrariums. They enjoy humid environments and don't like to dry out entirely.

This pack of terrarium plants from Walmart has a few different options to work with.

Something else to keep in mind is how much room your plants need to grow. Overcrowding terrariums can limit airflow and cause issues with mold. It's better to underplant than overplant your terrarium for this reason.

4. Add a Top Dressing

Optionally, you may wish to add some moss or pebbles to the top layer of your terrarium. This can provide a neater look, but also brings benefits to plant health.

Moss (like this pack of terrarium moss on Amazon) is moisture-retentive and works well for the moisture-loving terrarium plants, preventing them from drying out.

Plant pebbles (like these from Walmart) are much more common for succulent and cacti terrariums. This is because it acts as a protective barrier between the soil and lower succulent leaves, preventing issues of rot.

Pebbles can also help keep houseplant pests away, as it provides a barrier that stops them from laying eggs in the soil.

5. Place It Somewhere Bright

Another way to prolong your terrarium's lifespan is by maintaining optimal terrarium care. One of the most important elements of this is placing it somewhere bright.

Of course, light is essential for photosynthesis, which is vital for the plant process of absorbing carbon dioxide and releasing oxygen. In a terrarium, this helps maintain a stable mini-ecosystem for the plants inside.

Bright daylight not only helps plants grow, but it also aids moisture management, ensuring soil doesn't stay overly wet and reducing the likelihood of mold building up.

Plus, bright, even light will help terrarium plants stay compact, preventing leggy growth and sparse stems. Houseplant rotation is a good thing to practice to aid this.

In winter, you can supplement natural light with this grow light from Amazon. This is especially important when daylight levels are limited.

What to Shop

Our guide to where to place a terrarium has more information finding the right spot in your home. A bathroom can be a good location, with extra moisture and humidity from shower steam.

Love inspiring garden ideas, outdoor advice, and the latest news? Sign up for our newsletter and get the latest features delivered straight to your inbox.