Building a Self-Sustaining Terrarium
Good morning! Today I thought I’d explain how I make closed terrariums. They’re so amazingly beautiful!
A closed terrarium is different in that once you’ve finished creating it, you seal it up—and only very occasionally (if ever) open it. It is a self-sustaining mini ecosystem.
The water we add evaporates in to the air in the terrarium and condenses on the glass walls, then ‘rains’ back down to water the plants. My kids and I love to watch this process!
Rich well-draining substrate (soil) is a must. I mix equal parts sand, sphagnum moss and potting soil.
You’ll also need a base layer of either pea gravel or clay pebbles. This allows the water to sit at the bottom until the plants need it.
There are many different species of tropical plants you could use. I prefer to find 3-5. A mix of tall ferns and low creeping vines. Be sure to not add to many plant, as some will thrive and take over the others. Do not over stuff your terrarium with plants. A few plants can fill a terrarium in just a few months.
You can add a layer of carbon bits after your gravel layer and before your soil layer if you’d like, but I don’t feel it’s 100% necessary.
You’ll want to keep these out of harsh direct sunlight, but any well-lit room should be perfect.
Mold is going to happen, and it’s OK! It will go away after a bit.
Condensation should only be on the side of the jar facing the light source. If you notice condensation on all sides all the time, open your jar and let it sit a few days to a week to let some moisture out.
I used telescoping tools specifically for terrariums, but if those aren’t available to you, any long pointy object will work. Chopsticks, a bamboo dowel with a spoon taped to the end or a teachers pointer would all work well. I also made a funnel out of card stock to help me add the gravel and soil.
Step-by step DIY closed terrarium:
2”-3” layer of pea gravel or clay pebbles
Add water half way up gravel layer
3”-5” layer of soil mix (combine equal parts sphagnum moss, sand and potting soil)
Add 3-5 plants
Mist plants with spray bottle
Close terrarium
Set in a bright location
