Biotopia – terrariums
A miniature plant world
Caring for your closed terrarium
Here’s the good news: It’s quite easy!
The principle behind a terrarium is that it mimics nature’s own life cycle: The lid allows water to recycle itself, organic matter to be reused as plant food and helps it to maintain its humidity.
When all the elements come together, a closed terrarium requires very little maintenance apart from the odd prune or light mist of water.
Position/Lighting:
A semi bright spot, but out of direct sunshine as it can burn the plants through the glass. When you first put the lid on the terrarium, it will fog up, and gradually the fog will become water droplets on the glass. If you have had the terrarium for more than a month and the glass is always ‘sweaty’ on all sides, you may need to move it to a cooler spot. Make sure it is not in a position where it could overheat.
I repeat - Avoid direct sunlight!
Closed terrarium plants enjoy diffused or indirect light. If your plants look like they’re struggling, alternate your terrarium’s location from time to time.
Watering:
It’s very important not to over-water as this can lead to rot or fungus. Condensation is a good sign – it means your plants are breathing. A few sprays of water when there is no condensation or your plant is looking droopy are a good guide – once a month, even more rarely for containers with a good seal.
If the glass has condensation droplets on all sides, it may be too wet, leave the lid off for a little while, just not so long that it all dries out. You could also wipe down carefully with a paper towel.
Once the right humidity is established, a closed terrarium can go for several weeks between watering and in some cases months and even years! Closed terrariums actually thrive on neglect!
Cleaning:
If you feel the need to clean, just use a paper towel or cotton bud (but very gently and carefully so as not to damage the plants).
Pruning:
As the nutrients in the soil get used up, your plants’ growth will slow down. A little trim can bring them on, but can also promote side shoots. If you want to keep things ordered, remove all the vegetation that you cut. For that natural look, a self-sustaining terrarium is happiest growing wild.
Water: use filtered rain or distilled water to help keep your moss nice and green.
Air: Take the lid off for around half an hour, once a week to give your terrarium some fresh air.
Upkeep: Pinch off or trim leaves as they grow and touch the glass so they don’t go brown. Clean internal glass if needed with a paper towel.
Note & Queries
I cannot guarantee the terrarium’s longevity once it leaves my care. At the end of the day, your terrarium is filled with plants, and is not destined to live forever. If an element of your terrarium dies, despite your best care efforts, it may just be the cycle of life in action. Plants can always be replaced.