Want to learn more about Closed Terrarium Trivia
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A closed terrarium is a fun and easy way to grow plants. It is also the perfect gift as it doesn't require too much special care.
In this article you'll be getting our best tips and tricks on how to both create and care for your own closed tropical terrarium.
What is a closed terrarium?
A closed terrarium is an air tight vessel in which you grow a micro-ecosystem. It becomes its own self sustaining ecosystem that won't require any care or watering from you. Not even fertilizing or pruning is required. The soil, plants and microorganisms all work together to sustain a minature world.
Through photosynthesis, plants wick up water from the soil and release moisture and oxygen in the air through their leaves. Inside the enclosed terrarium, humidity builds up and begins to rain back down on the plants and into the soil. The plants will also loose some leaves naturally that will fall down and decay. Microorganisms in the soil will then help by breaking down organic matter into the soil which releases carbon dioxide and nutrients to the plants.
This terrarium contains Fittonia 'White Star', Soleirolia soleirolii, Nephrolepis 'Vitale', Pilea involucrata 'Moon Valley' and Syngonium podophyllum 'Neon'
Lighting is the most crucial part when it comes to caring for your closed terrarium. It needs plenty of bright, but only indirect light to thrive. If your planter is exposed to direct sunlight it can become too hot and even cook the plants inside the vessel. But if you place your terrarium in an area that's too dark, your plants won't be able to perform photosynthesis properly. It can cause the plants to grow very sparse and weak (called etiolation) which could even be fatal to the plants.
A spot where it'll be able to "see" the sky, but is protected from direct sun light, is best. If you live in a climate with less day hours during any season you might want to either move your planter to a brighter spot or supply it with grow lights during the darker season.
- Rotating your planter regularly is a good idea to maintain a thriving ecosystem if the light direction is only exposing one side of the vessel.
You only need to water and mist it once and that's when you create the ecosystem. So easy!
Pruning and fertilizing won't be necessary as it will be taken care of by the plants themselves. When they reach the top of the planter some leaves might start to wilt and the plants be naturally pruned. If the planter becomes overgrown some plants will die back when they get overshadowed by other plants. The wilting leaves and other organic matter will break down into new nutrients for the other plants.
This terrarium contains etiolated Fittonia 'Forest Flame', Cryptanthus bivittatus and a moss: Eucladium sp.
Want to create your own closed terrarium?
Then this is all you need:
Air tight vessel
Air tight vessel
You can choose any shape or type of vessel as long as it's see through and air tight. We recommend using one made out of glass as it's more durable, won't get discolored, doesn't age and doesn't get scratched as easily as a plastic containers. Mason jars, bottles, cookie jars, lanterns or even gumball machines can be used. Be creative and search through your home or a nearby thrift shop. There are also a lot of bottles available in garden centers that are made for just this type of project.
Glass bottles that have corks as a lid will lose water over time since it's not fully air tight. Once you've got a good humidity balance in your terrarium, you can either close it with wax, or add just a little water once or twice a year.
The drainage layer needs to be made out of minerals so it doesn't decompos. LECA, pumice, coarse sand and decorative gravels are just some examples of a suitable drainage layer. Adding a drainage layer will help your plants thrive and prevent watering issues. If you're vessel of choice doesn't have that much space you can skip this layer. But we recommend adding one if possible.
A light, fertile and fluffy soil type is suitable when planting your terrarium. Regular all purpose potting soil or a more tropical soil mix with coco coir and chunks of bark and perlite works as well.
Since you're creating a tropical environment it's important that you choose tropical plants. Succulents and cacti won't do well in your closed self sustaining terrarium. Also choosing plants that won't grow grow too large is advised.
Trees and shrubs with woody stems can be risky to use, both because they're often prone to grow very large and they're susceptible to stem rot if planted in excessively humid environments.
We recommend that you choose a mix of a ground covering plants, a taller plant and a color popping plant. Try to choose plants that contrast with each other to make the planter interesting and eye-catching.
- We will list suitable plants further down in this article if you need some inspiration.
How to create your closed terrarium
1. Start by adding a drainage layer at the bottom of the vessel-- layer of at least ½ in (1cm) if possible. If the vessel you use is big and has space you can increase the drainage layer accordingly. Try to keep it to 1/3 third of the total thickness of the bottom substrates.
- Optional: If you want to make it more advanced you can add a substrate divider to prevent the soil from blending into the drainage layer. A durable thin mesh, screen or even sphagnum moss can be used for this.
2. Add the soil of your choice and spread it out evenly on top of the drainage layer. If you have a larger vessel you can try to create a slope or make the center higher to create a more interesting design. Make sure it'll have space for the roots of your plants.
- Optional: You can also add rocks, wood, figurines, sea shells or other objects to decorate the terrarium with. Some will also be excellent to use as support for climbing or epiphytic plants.
3. Now it's time for the plants! We recommend starting with the outer plants first and then working your way to the center of your creation, especially if you're working with a vessel that has a narrower neck.
Remove most of the old soil fromt the roots of the plants. Lots of plants can be divided or have several plants in the same pot. Divide them to help spread them out more. You don't need to fill out all the free space as the plants will grow.
4. Finish up the planter by cleaning the inside walls of the vessel and brushing off the foliage. Water the plants by misting them with a spray bottle. This can also help to clean off the last dirt from the plants and the walls of the vessel. When the plants are watered enough and it's clean it's time to close it up!
The upcoming week you'll have to keep an eye on your closed terrarium to ensure that it's been watered enough. You want some condensation to build up but not too much. If you notice that the condensation covers the entire planter you need to open up the terrarium for a couple of hours to allow some excess water to evaporate. Close it up again and enjoy your own ecosystem.
- Note that it's perfectly normal for small microorganisms to thrive in your planter. Spring tails and wood louse are not uncommon to have in your closed terrarium. They are totally harmless and nothing to worry about. In fact, they are beneficial.
5. You can add your closed terrarium to Planta if you want to follow its progress.
This terrarium contains Pteris ensiformis, Philodendron hederaceum 'Brasil', Alocasia 'Bambino', Callisia repens, Peperomia prostrata, Fittonia 'White Tiger' and 'Pink Angel'
- "sp." meaning there are multiple suitable plants within that genus.
Low growing and ground covering plants
Ficus pumila, Creeping fig
Pilea libanensis, Silver sprinkles
Callisia repens, Turtle vine
Soleirolia soleirolii, Baby tears
Selaginella kraussiana, Krauss' spikemoss
Pilea depressa, Giant's baby's tears
Peperomia prostrata, String of turtles
Different types of tropical mosses
Ferns to add texture
Selaginella sp. - Not a fern but a spikemoss and adds similar texture to the mix
Hemionitis cordata, Heart leaf fern
Pellaea rotundifolia, Button fern
Actiniopteris australis, Eyelash fern
Medium sized plants to add interesting foliage and color
Fittonia sp., Nerve plant
Syngonium podophyllum, Arrowhead plant
Epipremnum aureum, Pothos
Philodendron hederaceum, Heart leaf philodendron
Alocasia sp. - Choose smaller sized species and cultivars such as 'Bambino', 'Black Velvet' and Alocasia maharani
Macodes petola, Lighting bolt jewel orchid
Ludisia discolor, Jewel orchid
Hypoestes polystaycha, Polka dot plant
Clorophytum comosum, Spider plant
Pellonia repens, Trailing watermelon begonia
Gynura aurantiaca, Purple passion
Maranta leuconeura, Prayer plant
Goeppertia sp. (Formerly known as Calathea)
Murdannia sp. 'Bright Star',
Cercestis mirabilis, African embossed cercestis
Cissus amazonica, Amazon jungle vine