Terrariums are miniature gardens in a large glass or plastic jar. When I was first married and we lived in a small apartment, I took a class on making terrariums. It was how I first gardened without any gardening space.
Done right, terrariums become miniature environments that are self-sustaining and need very little care from the gardener. They are fun to create, too.
Start by choosing an appropriate jar. I have seen beautiful terrariums in old fish tanks, kitchen canisters, and a large glass water bottle. The sky is the limit actually for jar choices, but don’t choose a jar with colored glass. You need it to be clear glass so that all of the normal rays of the sun can travel through the glass. In addition, your jar should be big enough to comfortably hold 3-5 small plants.
If you jar has a large opening, you will need a cover for it, but you can use plastic wrap if necessary. You are actually creating a miniature green house and the environment within the jar will be different than your normal house environment if you keep a top on your container.
Before you start building your terrarium make sure your container is clean and dry. If possible wash it in your dishwasher and use the sanitize option.
Next, you need pea gravel or very small stones for the bottom layer of your terrarium. This layer is necessary for water drainage. Your gravel layer should be between ½ to 1 inch thick and you might want to save some of your pebbles for paths or decorations when you finish your terrarium.On top of the gravel spread two to three inches of potting soil. It doesn’t all have to be level either. You can create some deeper places to simulate natural hills and valleys in your terrarium landscape. Some people like to line the glass with sheet moss for a neater appearance but this isn’t necessary.
You’ve probably realized by now that it can be a little tricky building a terrarium and you would probably benefit from some special tools. When I took my terrarium class, the teacher had us make all our own tools and some of the things people came up with were very creative.
Things I found helpful were ice-tea spoons, chopsticks, barbeque tongs, and long straws. One man in my class bought dowels and attached a fork head to one and a teaspoon to another. Artist paintbrushes are useful for brushing dirt off the sides of the jar and a turkey baster is helpful to water your terrarium. Corks attached to dowels or straws are good for tamping down the soil and making hills or paths. If the neck of your bottle is narrow, flexible wire is sometimes helpful to have.
Once you’ve placed the potting soil in your terrarium, it’s time to add your plants. Hopefully, you’ve put some thought into the selection of your plants and they all have similar environmental needs. Plants should be as small as you can get them-no larger than 2 ½ inches if possible and for the best appearance choose at least one tall, one medium and one short growing plant.
The best plants for terrariums are slow growing ones, but because the conditions are so ideal, even these plants will grow and eventually you will have to figure out some way to trim them to maintain their good looks.
Dig holes with long handled spoons to place your plants starting with the tallest ones first. Add decorative elements such as bridges or figurines at the same time as you add your plants. Sand or gravel can be used for paths.
Add more potting soil if necessary to completely cover the roots of your plants and tamp down gently. Cover the soil with another layer of moss if desired. Use your paintbrush to tidy up pot soil crumbs on the glass before your water your terrarium.
You do not need a lot of water in a terrarium so start out slowly. Use your straws or your turkey baster to put a little water around the base of each plant. Try not to get the glass itself wet. Now cover your terrarium and put it where you can watch it closely for a few days. Any tabletop is fine where you have bright but not direct light. Do not ever put your terrarium in direct sunlight, though, because it can get too hot inside your jar and actually burn your plants.
If your terrarium has enough water you should start to see tiny water droplets collect at the top of the jar because you have created a rain cycle. Too much water will make the jar fog up and then you need to take the top off until it dries out a little.
As long as you can see a little water condensing on the top of your terrarium you do not need to water it, but when you do only give it a tablespoon or so at a time. The plants themselves give off moisture and the trapped moisture is reused to keep the soil damp.
Terrariums can be quite beautiful and if you enjoy making them they can also be wonderful gifts and no two are ever alike. So there you have it, a beautiful terrarium, and a creative gardening project to fill up these dreary winter days with. Have fun and thanks for gardening with Julie.
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