Terrarium making

5 Common Mistakes to Avoid When Building a Terrarium

Creating your own small indoor garden in a terrarium can be a wonderfully rewarding experience. These miniature gardens are not only beautiful but also low-maintenance, making them perfect for busy lifestyles. However, there are a few common pitfalls that many beginners encounter when building their first terrarium. To help you succeed, we've compiled a list of five common mistakes to avoid when building a terrarium.

1. Choosing the Wrong Plants

One of the most crucial aspects of a successful terrarium is selecting the right plants. Not all plants thrive in the same environment, and this is especially true in the confined space of a terrarium. A common mistake is mixing plants with different humidity and light requirements. For instance, combining succulents, which prefer dry conditions, with mosses that thrive in humidity, can lead to disaster for one or both types of plants.

Tip: Stick to plants with similar needs. For a humid, closed terrarium, consider ferns, mosses, and fittonias. For an open, dry terrarium, succulents and cacti are your best bet.

2. Using Poor Quality Soil

The soil is the foundation of your terrarium, and using the wrong type can spell trouble for your plants. Regular garden soil is often too dense and retains too much moisture, leading to root rot. It can also be filled with pests and pathogens that can harm your plants.

Tip: Invest in high-quality potting soil suited to the plants you’re using. For succulents, a mix of cactus soil works well, while tropical plants prefer a soil mixed with perlite for better drainage.

3. Overwatering

Overwatering is one of the most common mistakes in terrarium care. In a closed environment, water doesn't evaporate as quickly as it does in open air, and excess moisture can lead to mold, mildew, and root rot.

Tip: Water sparingly. It's better to under-water slightly than to overdo it. Use a spray bottle to lightly mist the soil, moss and plants, and always check that the soil is dry before adding more water.

4. Incorrect Lighting

Terrariums need the right amount of light to thrive. Too much direct sunlight can scorch the plants and cause the glass to overheat, while too little light can result in weak, leggy growth. Additionally, it can affect the condensation levels in your garden in a bottle. Finding the right balance is key.

Tip: Place your terrarium in a spot where it can receive indirect light. East or north-facing windows are often ideal. If natural light is insufficient, consider using a grow light to provide the necessary illumination without the risk of overheating.

5. Neglecting Ventilation

While closed terrariums are designed to create a self-sustaining environment, they still need occasional ventilation to prevent the build-up of excess moisture and to refresh the air inside.

Tip: Every few weeks, open the lid of your terrarium for some time to let it breathe. This simple step can help prevent mold growth and keep your plants healthy. For open terrariums, ensure they are in a well-ventilated area to maintain air circulation.

Building a terrarium can be a delightful and creative project, but avoiding these common mistakes is essential for success. By choosing the right plants, using appropriate soil, managing water levels, providing adequate light, and ensuring proper ventilation, you can create a thriving miniature ecosystem that brings a touch of nature into your home.

For more tips on terrarium building and plant care, be sure to check out our blog. And if you’re looking to start your own terrarium, browse our selection of DIY Terrarium Kits with FREE delivery on orders over £50!

Happy planting!