DIY: Terrariums

Above: my prehistoric terrarium with tropical plants and live moss.

My mom, sister-in-law and nieces got together this weekend for a terrarium-making party at my house.  It was good times!  Terrariums are simple to make, low maintenance, and great for small spaces.  You can fit an entire self-contained garden on a tabletop or desk with ease.  Plus, they're super cute, am I right?  

Materials

• Glass containers
• You can buy either open or closed containers.  However, I would not recommend a closed container for cacti/succulents, as humid conditions will promote rot.  Tropical plants are suited for closed containers.
• Plants
• Only mix plants that have similar light, soil, humidity and watering requirements, i.e. mix tropicals with other tropicals and cacti/succulents with other cacti/succulents.
• Potting soil
• Small rocks or gravel
• Activated charcoal or carbon
• I bought mine at a pet store 
• Sand (optional)
• Live moss (optional)
• I've read that mixing preserved moss with live plants is a recipe for moldy plants, and my own experience has proven this to be true; I bought a small terrarium at a craft show that molded over in three weeks on account of its preserved moss + live plants combination :-/.  Thankfully, I was able to remove the live plants and save them :)
• Decorative items (optional)
• Small plastic animals, seashells, sticks, gems, minerals, etc.  We bought our items at a craft store.  I found the little plastic dinosaurs pictured in a dollar bin at Target.

Instructions

• Create the substrate, or drainage layer.  Your terrarium has no source of drainage, so you'll need to make one yourself:
• Add a scoop of gravel
• Add a small amount of activated charcoal
• Add one or more layers of sand (optional).  We bought two different colors of sand for visual interest.
• Add potting soil.
• Carefully add your plants.  Do not let the leaves touch the sides of the container because the moisture on the glass will cause mold or rot.
• Top the soil with small rocks or gravel for a finished look (optional)
• Arrange your decorative items to your liking.

Top picture: Marisor, my sister-in-law, with my nieces, Hanna and Leah.  

Bottom picture: my mom :)

Maintenance

• Err on the side of less watering.  As a general rule, closed containers require less watering than open containers for obvious reasons.  
• Check the soil every two weeks or so to determine whether you need to water your terrarium. For tropicals, if the top layer of soil is dry, it's time to water your plants, but sparingly.  For cacti/succulents, let the soil dry out completely in between waterings.
• Some condensation indicates adequate moisture.  However, if condensation covers more than 25% of your terrarium walls, there is excessive moisture, and the conditions in your terrarium will encourage mold.  If you have a closed container, remove the lid until the condensation clears.  
• If leaves look pale or dry, add more water and mist plants.
• Do not fertilize your terrarium because the idea is to keep the plants small and container-sized.
• Prune plants as needed to maintain your plants' compact size, or to remove yellowed/damaged foliage.

My niece, Hanna's, jungle themed succulent terrarium.

My mom's cactus/succulent dish garden.  She used the same steps outlined above to create this dish.

My niece, Leah's prehistoric succulent terrarium.