Building an Emergent Terrarium
Welcome to COSMs Guide to building an Emergent Terrarium
To begin with we'll need to talk a little about what exactly an Emergent Terrarium is. The word "emergent" is used to refer to aquatic plants that grow or emerge out of water. These plants have developed in this way so that they can breach the surface of the water and gain more access to CO2 and sunlight to fuel their growth. However, since they're aquatic plants, they still require humid air when grown out of water, making them perfect for terrariums.
Step 1: Pick your Jar
Firstly, every terrarium starts with a jar! Find one you like, any size and any shape will do. Just make sure you keep in mind how large these plants may eventually begin to grow; how much trimming will you have to do if the jar is too small? or how long it may take to "fill out" if the jar is too big?
The one condition that needs to be met is that it must be sealable to lock in all of the moisture needed in the air for aquatic plants to grow emergent forms.
Step 2: Lay your Gravel
Once you've found a jar that fits perfectly on your shelf, night stand or window sill; we must add an inert false bottom. Pebbles, gravel, sand, marbles or even crystals if you wish. In most Terrariums the purpose of the false bottom is so that excess water can drain out of the soil saving plant roots from rot and decay. In an Emergent Terrarium however root rot is not a problem as these plants are accustomed to growing completely submersed. Here the false bottom serves the purpose of harboring water to keep the air in the Terrarium humid. To keep the false bottom separate you may place a semi-permeable layer above it, a piece of felt or cloth for example, this however is optional.
The false bottom may also include purifying substances like charcoal which binds and holds molecules that form from decay that ca build up or may cause bad smells. This is also optional.
Step 3: Add your Soil layer
The Third step in this process would be to place your layer of soil. Any basic soil or potting compost will be fine. Good moisture retention is very important as these plants are used to an underwater environment. It would be great idea to mix in a little coco coir or peat moss to help with that although it isn't a necessity.
Top tip: It would be great to slope the soil towards the front of the jar for better viewing angles!
Step 4: A little Décor
This next step is totally optional as plant only Terraria can be just as beautiful as decorated ones. If you would like to you can add various types of hardscape material like rock, wood or crystals. In actual fact you can place any item that tickles your fancy so long as it wont get damaged by the moisture or release harmful substances into the environment.
This is where the artistic element first comes into play as the hardscape (if you choose to add any) frames the terrarium, creates visual lines or can form the terraces and placement spots for your plants.
Step 5: Time to plant
Now whether you chose to follow the last step or not this fifth step is what we're all here for. It's time to add the plants! This sounds like the easiest step but it is the step which probably requires the most thought. You must think about the arrangement of Foreground, Midground and Background plants and place them in a way in which one won't be shaded to death by another. You should think about how it will look when fully grown in. If planted haphazardly some plants may thrive but not be visible or hang over into the foreground in an unsightly manner or even just die off due to being misplaced. Terrarium building is an art of patience though; you can let plants grow in then trim or replace them as you see fit. Observe the plant growth and make the decisions that enrich the terrariums inhabitants aswell as the time you spend observing it.
Step 6: Spritz and Seal
When you've finished planting, all that is left is to mist your terrarium and close it up to lock in that moisture. Be sure to place the terrarium under a spotlight or in a bright spot. Most plants can tolerate lower light but every plant will enjoy the most light you can give it.
Step 7: Be the Master of your Micro-COSM!
At this stage your Emergent Terrarium is essentially finished. The final step is continuous and consists of regular husbandry. Trimming and remoisturising to keep the environment inside of your micro-cosm healthy. Observing and appreciating the growth that occurs inside. Always trim, the act of trimming alone makes your plants grow nice and bushy, giving you more growth points from which you can propagate and plant new terrariums. When you trim you can replant cuttings to thicken any bare patches. The more you trim and replant, the more your terrarium will fill out and look amazing!
