1. Cut the vinyl.
Note: Since this project is made with clear vinyl, which is nearly invisible in photographs, I’m demonstrating these steps using paper.
To begin, we’ll look at how to make the rectangular terrarium. Cut a piece of vinyl that’s the desired width of your finished container plus two times your desired height, by your desired length plus two times your desired height. Add 1/2″ to each side for seam allowance.
Next, measure a square section on each corner that is the size of your planned height for the container. So, if you planned a height of 3″, measure a 3″ square from each corner. (Note: You can draw guide lines on the vinyl with marker; they will easily wipe off. Of course, you should test this on your vinyl first. Also of note: A gridded cutting mat makes it really easy to measure your vinyl accurately.)
Cut out the corner sections.
2. Prepare the tissue.
Because vinyl is difficult to sew on a machine (its stickiness won’t allow it to feed through the machine properly), the solution is to sandwich the vinyl between strips of tissue paper. Cut several 1″ strips of tissue and set aside.
3. Sew the corners.
Fold the vinyl at each corner so that the edges of the cut-out section meet. Place the folded vinyl between two strips of tissue paper, and secure all layers with paperclips.
Sew the corner seam, using a 1/4″ seam allowance.
Tear away the tissue paper. (If it gets stuck under the thread in any spots, pull it out with tweezers.)
Sew all four corner sections, and your finished container will look like this!
4. Waterproof the seams.
Not surprisingly, a sewn seam will not be waterproof. This is not a major concern for this project, since terrariums are meant to be only slightly damp, not soaked with water — so leaking shouldn’t become a big issue. I recommend keeping your finished terrarium on a plate or platter at all times to catch any possible dribbles, but if you like, you can make the seams a bit more water-resistant by running a bead of hot glue along the inside of each seam. The glue will be somewhat visible, so it becomes an aesthetic choice as to whether you want to include this step.
And that’s it; your container is done! Place it on a platter, and fill it as you wish! I’m not an expert on planting, but here’s how I make my simple terrariums: a layer of pebbles, a layer of activated charcoal (this is really only needed in a closed or mostly-closed terrarium), a layer of potting soil and a piece of moss. I find that moss is easy to grow compared to some other plants and has a wonderfully lush texture that looks great. Then, just mist the terrarium whenever it looks dry. For my terrariums with lids, I never have to water them; but styles like these with an open top will need to be watered occasionally.
Variation 1: Slanted sides
To make the container with slanted sides, cut the corner sections at an angle greater than 90 degrees. Wider angles will create a steeper slant. Then sew each corner as described above.
Variation 2: Round, fluted container
To make the round container, cut a circle with a diameter equal to your desired base size, plus two times your desired height. (The circle doesn’t have to be absolutely perfect.)
Make small folds along the edge of the circle, sewing each in place. (My dotted line in this photo indicates where you would sew the seam.) Repeat all around the circle, and don’t worry about making each fold to an exact measurement — an abstract result works just fine here!
You’ll need a few tools to make a tiny terrarium but nothing complicated to get started.
Let’s start with the light bulb. I like the globe kind that are used to light bathroom vanities. You can buy them at any hardware store, or preferably, use one that’s burned out to save resources. For those of us in northern California, one option for buying burned out bulbs (if you don’t have any on hand) is the East Bay Depot for Creative Reuse in Oakland. Don’t use “soft white” bulbs or else your terrarium will just look like January in Minnesota. I don’t think this is what you’re going for.
We will be removing the inside parts of the lightbulb. This step involves breaking glass, so wear glasses or goggles to protect your eyes. I recommend doing this over a box to contain any flying pieces of broken glass. And, obviously, this is an “adults only” kind of task.
First, remove the metal tip from the bottom of the bulb. Using needle-nose pliers, carefully nudge the sides of the metal tip from the black glass part.
Then, when enough of the sides are raised to get a good grip on them, hold one of the sides with your pliers and yank out the metal tip. You will feel a couple little wires snap when you do this.
Next remove the black glass. Hold one side of the glass with the pliers and firmly twist up to snap the glass. Repeat around the other sides and pull out any remaining bits of black glass. This glass is pretty thick and will take some force to break it; so be careful and hold onto the bulb firmly.
Now you will be able to see the interior parts of the light bulb.
Using the flathead screwdriver as a sort of lever, snap the interior tube from the side. It will make a totally satisfying little sound as the argon escapes. Then twist the screwdriver around to smash the containing tube. It takes some force to do this; be careful, but also don’t be afraid of the bulb itself breaking. It probably won’t. Hold tight to the bulb while you do this.
Pull out any remaining wires with the pliers.
If there are any last bits of glass around the interior edge, break these off with the screwdriver.
And now you have an empty light bulb! That is definitely the hardest part of the endeavor. Next, put adhesive silicone bumpers on the side of the bulb to keep it steady.
We’ll use sand as a substrate for the terrarium. You can buy it at a garden store or collect it from a beach. If you use beach sand you will need to thoroughly rinse it to remove any salt.
The sand in this tutorial is from the beach, so our first step is to rinse it.
To dry it, either spread it in a thin layer on a cookie sheet and leave it sitting for a few days, or dry it in the oven at 300 degrees. Be careful taking it out, because it will, hopefully obviously, be pretty hot.
The sand should be completely dry before continuing.
Once it’s dry, put a couple tablespoons of sand into the lightbulb. Make this easier by either using a funnel or a folded piece of cardboard.
This terrarium includes preserved sheet moss, reindeer moss, and tillandsia.
Cut off a small bit of sheet moss and put in the bulb. Position it using a chopstick or long tweezers. Tear off a few small pieces of reindeer moss and add this, as well.
Put a tillandsia in the bulb, pushing the smaller end in first. Position the different elements to look nice together and add more moss or rocks if you’d like. It might take some poking to get everything in the right place; be patient and experiment with different arrangements.
For extra fun, tiny toy animals can enliven your terrarium. I used a miniature horse for this one, and stuck a piece of gold wire in its head to make it into a makeshift unicorn. Any other found objects, like rocks, sticks, marbles, etc., would also be fun.
And voilà! You have a lovely terrarium.