Making a terrarium, a self-sustainable ecosystem with a living, growing plant inside a sealed bottle, is a pretty easy project and the plant growing inside can survive for decades without any watering or other care. Here’s how you can build a terrarium on your own.
How to make a terrarium, vivarium, or garden in a bottle
- First, find a suitable sealed glass bottle or jar. A bottle with a wide mouth will be much easier to work with. Make sure the bottle has a lid or cork which can be sealed tightly.
- Fill the bottom of the bottle with pebbles. You need at least enough pebbles to cover the bottom of the bottle but can add more if the bottle is taller. Try to fill about 1/5 of the bottle with pebbles. The pebbles will provide a space for water to collect in. Colorful, polished, pretty pebbles can be purchased at a pet store (they use them in fish aquariums).
- Cover the pebbles with a thin layer of activated charcoal. You can usually find activated charcoal at a pet store. The charcoal will filter impurities out of the water and will serve to keep the terrarium clean.
- Add a ½ inch layer of peat moss (a type of very nutritious soil) on top of the activated charcoal. The peat moss will hold water and nutrients that the plant needs to grow.
- Add a ½ inch layer of potting soil on top of the peat moss. This is the dirt that our plant will stake its roots into.
- Take a piece of moss, with some soil still covering its roots, and carefully place it on top of the soil in your bottle. If the mouth of the bottle is too small to reach into, use tweezers, chop sticks, a Popsicle stick, or some other means (Reeko uses a well-behaved, specially trained ant who is very good at following directions) to lower the plant down into the bottle. Spray a bit of water on it – by now it’s probably pretty thirsty.You can collect moss from outside. Look for it in places that have just a little bit of sunlight shining on them. Dig up a small moss patch and place it inside a plastic bag or sealed plastic container so it does not dry out before you can plant it.
- Before placing the lid/cork on the bottle, clean the inner glass so it’s easy to see through. You can attach a cotton ball or small piece of cloth to a stick that you can reach down into the bottle to clean the bottle’s sides.
- Place the lid on the bottle and seal it up tight!
Finally, place the bottle in a fairly sunny spot. The moss will need sunlight to grow but not as much as some plants. If there is too much sunlight shining on your terrarium, it will tend to dry out. Not enough sunlight and the plant will not live. Somewhere around a window, but not directly in the sunlight, will work best.
If the inside of the bottle seems to be too wet, leave the lid off for a day or two to let it dry out. Similarly, if it seems to dry, remove the lid and add just a tiny amount of water to the terrarium.
The “gap of air” in the bottle should be about 2/3 of the available space. That means 1/3 of the height of the bottle should be filled with pebbles and soil and about 2/3 of the height of the bottle should be empty space for the plant to grow into.
Sometimes moss and soil can have bugs or bug eggs in it which you might notice after the bottle is sealed. Be nice and let the little critters out.
Check out this story about a guy that created a terrarium that has not been watered in over 40 years and how photosynthesis works in a terrarium.
Supplies: Glass bottle, pebbles, activated charcoal, peat moss, potting soil, moss