Top 5 Most Popular Questions About Terrariums (Answered!)

Terrariums are a beautiful and low-maintenance way to bring a touch of nature indoors. Whether you're new to the world of terrariums or just looking to improve your green thumb, you're not alone in having questions. Below are the five most common questions people ask about terrariums—answered simply and clearly.

1. What is a terrarium, exactly?

A terrarium is a small, enclosed (or sometimes open) glass container that holds plants and creates its own little ecosystem. Think of it as a miniature garden. There are two main types:

• Closed terrariums – These are sealed and ideal for moisture-loving plants like moss, ferns, and fittonia.

• Open terrariums – These allow airflow and are perfect for succulents, cacti, and other dry-climate plants.

Terrariums are especially popular in cities like London, where outdoor space is limited, and people are looking for creative ways to bring greenery indoors.

2. Do terrariums need sunlight?

Yes, but not direct sunlight! Most terrariums thrive in bright, indirect light. Direct sun can heat up the glass and damage your plants. If natural light is limited, a grow light can be a good alternative. Always match light conditions with the type of plants you choose.

3. How often should I water my terrarium?

It depends on the type:

• Closed terrariums – Rarely need watering (every few weeks or months) because they recycle moisture.

• Open terrariums – Open terrariums require more frequent watering, but the exact amount depends on the type of plants inside. Always check the soil moisture and monitor your plants for signs of dryness or excess water.

Tip: If there's condensation on the glass of a closed terrarium, it’s doing fine. If it's bone dry, give it a little water.

4. What kind of plants work best in terrariums?

The best plants are small, slow-growing, and suited to the humidity level of your terrarium. Some popular choices include:

• For closed terrariums: Moss, ferns, nerve plant (fittonia), gynura, pilea molis or small Ginseng Bonsai. 
  

• For open terrariums: Succulents, cacti, air plants, jade plant, echeveria.

Avoid mixing moisture-loving and drought-tolerant plants in the same container—they have very different care needs.

5. Why is my terrarium foggy or molding?

Foggy glass is usually harmless condensation. But mold is a problem and often caused by:

• Overwatering

• Lack of airflow

• Too much organic matter

T o fix it, remove dead plant material, reduce watering, and open the lid occasionally if it's a closed terrarium. Activated charcoal should be included as one of the layers in your terrarium, as it helps prevent mold and unpleasant odors.

Ready to Start Your Terrarium Journey?

If you’d like to create your own miniature garden, visit our Terrarium Section—your one-stop shop for everything you need. From DIY kits, premium soil mixes, activated charcoal, moss, and terrarium-friendly plants, we’ve got you covered.

Whether you're in London or beyond, you can start building your tiny world today—it's easier than you think, and endlessly rewarding.