Succulents are popular plants for a terrarium because they are easy to care for. Their small scale works well in tiny enclosures, and makes it easy to create a miniature desert landscape in your home. However, they require different growing conditions than ordinary house plants, and require a little extra consideration when planning your terrarium.
Succulents are slow growing plants that don't need a lot of water. Although this makes them easier to care for, it also makes them susceptible to over watering, which is the number one reason many succulents do not do well in homes.
The first step in building your succulent terrarium is to choose your plants. Try to vary the shape and texture of the plants you choose. This will help create an interesting arrangement. Choose plants that grow at a similar rate and require similar amounts of light and water. Try Echeveria, Sempervivum, Jade Plant, and Blue Star Sapphire plants.
Next, choose a container for your terrarium. Look for a clear glass or plastic container. Here's one area where a succulent terrarium differs from a traditional terrarium. Succulents are desert plants, and don't like high humidity, so a closed container is not a good choice here. Choose a container with a wide opening to help with air circulation.
Place 1-2 inches of stones or small pebbles in the bottom of the container. The stones create a place for excess water to drain into, which is important for succulents. It's also a good idea, though not required, to add a thin layer of activated charcoal on top of the pebbles. You can buy activated charcoal at any aquarium store. The charcoal helps keep your terrarium fresh and discourages mold.
Now add a few inches of cactus soil over the stones. Don't use regular potting soil. Cactus soil provides better drainage and is more suited to desert plants. Place your plants in the soil, and add additional soil around them to anchor them in. If any leaves fall off while you are planting, don't throw them out! Most succulents can grow a whole new plant off a single cutting. Place the fallen portion into the dirt, and with any luck you'll have a brand new plant in a few weeks.
Many people like to add a layer of sand on top of the soil to create a desert look. This isn't necessary, but if you would like a layer of sand add it now. You can even use a straw to gently blow windswept bluffs across your sand! You can also add any decorations now, like rocks, glass beads, or small figurines. Be creative and use your imagination!
Caring for a succulent terrarium is simple. Place it in a sunny spot, but make sure the sun doesn't reflect through the container glass and cook your plants. Water the terrarium every 2 weeks. Remember, don't over water it! The soil should feel completely dry before you add more water.