How to choose the right terrarium
Updated June 2026Independently researchedNo paid placement.
The best terrarium for you depends on whether you want an open, low-maintenance succulent garden or a closed, self-watering moss and fern ecosystem. Look for a glass container with a wide opening for easy planting, or a tight-fitting lid for a truly closed setup, and match the plants to the light your home offers.
What is a terrarium and why should you buy one?
A terrarium is a miniature garden grown inside a glass container. It’s a self-contained ecosystem that brings a slice of nature indoors, requiring far less attention than a typical potted plant. Open terrariums are great for succulents and cacti that like dry air, while closed terrariums recycle moisture and are perfect for ferns, mosses, and tropical plants. Beyond the aesthetic appeal, terrariums are a practical choice for small spaces, offices, or homes with pets that might nibble on houseplants. They also make thoughtful gifts for plant lovers or beginners because they’re forgiving and visually striking. The key is choosing the right type and setup for your environment.
Open vs. closed terrariums: which should you choose?
Open terrariums have no lid, so they allow air circulation and let the soil dry out between waterings. They’re ideal for succulents, air plants, and cacti that thrive in bright light and dry conditions. The downside is that they need more frequent watering and are more prone to dust and pests. Closed terrariums have a fitted glass lid or cork, creating a humid, self-regulating environment. They’re perfect for moisture-loving plants like ferns, mosses, and peperomias. Once established, they can go weeks without watering, but they require careful drainage and occasional airing to prevent mold. If you travel often or forget to water, a closed terrarium is usually the smarter pick.
What size and shape of terrarium container is best?
The container’s size and shape directly affect how easy it is to plant and maintain. A wide-mouth jar, bowl, or apothecary jar gives you room to arrange plants and reach in for pruning. Narrow-necked bottles look charming but are difficult to plant and clean, unless you’re prepared to use long tweezers and a steady hand. For beginners, a medium-sized container with an opening at least a few inches across is a safe bet. Larger containers hold more soil and plants, which means more stable humidity and less frequent watering. Just remember that the bigger the terrarium, the more space it takes up, so measure your shelf or table before buying.
Which plants are easiest to grow in a terrarium?
For open terrariums, choose succulents like echeveria, haworthia, or jade plants, along with air plants (tillandsia) that don’t need soil. These plants prefer bright, indirect light and dry out between waterings. Avoid mixing them with moisture-loving plants, as their watering needs clash. For closed terrariums, go with ferns, mosses, pilea, fittonia, or baby’s tears. These plants love humidity and low to medium light, making them perfect for a sealed glass world. Stay away from fast-growing or large plants that will quickly outgrow the container. Always check the plant’s mature size and growth habit before planting.
How do you set up a terrarium for long-term success?
Start with a clean, dry container. Add a drainage layer of small pebbles or gravel, then a thin layer of activated charcoal to keep the water fresh and prevent odors. Top with a layer of sphagnum moss to stop soil from sifting down, then add a well-draining potting mix suited to your plants. Plant your chosen plants, leaving space between them for growth, and mist lightly. For closed terrariums, wipe the glass and place the lid on. For open ones, water sparingly and place in bright, indirect light. Monitor for condensation in closed setups, if it’s excessive, open the lid for a few hours. Overwatering is the most common mistake, so when in doubt, water less.
What are the best terrarium brands and kits?
Several reputable brands make quality terrarium kits that are perfect for beginners. For glass containers, look for options from H Potter, which offers elegant geometric and apothecary-style jars. For complete kits, consider Back to the Roots, which includes seeds, soil, and a container, or Plants for Pets, known for their self-contained closed terrariums. If you prefer to build your own, you can buy a plain glass container from a home goods store and pick individual plants from a local nursery. That approach often gives you more control over size and style. Read owner reviews to gauge durability of the glass and how easy the kit is to assemble. Avoid kits with poor drainage or overly complicated instructions.
Frequently asked questions
How often should I water my terrarium?
Open terrariums with succulents need water every one to two weeks, only when the soil is completely dry. Closed terrariums may need water only once a month or even less, because they recycle moisture. Always check the soil moisture before watering.
Why is there mold growing in my closed terrarium?
Mold usually appears when there’s too much moisture and not enough air circulation. Remove the lid for a few hours to let it dry out, and reduce watering. If mold persists, remove the affected plant or soil and replace with fresh, dry material.
Can I use any glass jar as a terrarium?
Yes, any clear glass container with a wide enough opening for planting can work. Just make sure it’s clean and has no cracks. For closed terrariums, you’ll need a lid that fits snugly, like a cork or a glass top.
What is the best light for a terrarium?
Most terrarium plants prefer bright, indirect light, such as near a north or east-facing window. Avoid direct sunlight, which can overheat the glass and cook the plants. If natural light is limited, a grow light can work well.
Do terrariums need fertilizer?
Generally, no. Terrariums have limited soil and plants grow slowly, so fertilizer can cause excessive growth and salt buildup. If you notice yellowing leaves, a very diluted liquid fertilizer once a year is enough, but most terrariums thrive without it.
How long do terrariums last?
With proper care, a closed terrarium can last for years, even decades, as a self-sustaining ecosystem. Open terrariums with succulents may need replanting every couple of years as plants outgrow the container. Regular pruning and cleaning extend the life of any terrarium.