Note: This column was published in the Barrow Journal on March 27, 2013.

If you’re eager to plant some greenery, but you’re still waiting for the threat of frost to pass, you might enjoy making a terrarium for inside the house. My plant-loving six-year-old found instructions in First Nature Activity Book by DK Publishing, and he asked if we could make one. I didn’t see why not.

Luckily for me, it’s fairly simple to make.  Here’s what you need: a clear container with a wide neck and an air-tight cover, small pebbles, charcoal, peat-based potting soil, small ferns, different types of moss, lichen-covered twigs or bark.

We had the charcoal, and we had plenty of moss, lichen and small ferns growing in shady spots in our yard, but we didn’t have the other ingredients. At the garden store, I bought a bag of pebbles and the peat-based potting soil. At the pet store, I found a medium-sized Kritter Keeper, and I lined the top with cellophane to make it airtight. A decorative glass container would be prettier but more expensive, or you could easily use an old aquarium.

When you let the kids do the work, they have fun cleaning up after themselves. (Sometimes.)

First, line the bottom of the container with enough pebbles to cover it evenly.  The pebbles are there for drainage. Next, add a layer of charcoal. We put in a fairly thin layer, but we covered the pebbles completely and evenly.

This is not the way I recommend you put in the charcoal. By pouring it in, it covered the walls with black soot and we had to clean them. Just be more careful.

My six-year-old had fun when I put some pieces of charcoal in a baggie and let him pound them on the sidewalk with a hammer to break them into tiny pieces.  The charcoal is supposed to act as a filter, keeping the terrarium smelling good. I have read different opinions online about whether it’s needed or not, but for a closed terrarium, it’s probably a good idea.

Next, add a thick layer of the peat-based potting soil, but leave plenty of space for the plants. Now the terrarium is ready for the plants.

We had to do some trimming.

We found all our plants in our yard. There was a small, pretty wild plant growing next to our house under the monkey grass, and I never had the heart to pull it out. I thought we’d give it a chance in the terrarium even though I have no idea what it is.

I also found an offshoot of some Japanese painted fern, which I had planted years ago near our front porch.  My six-year-old and three-year-old had a great time going around the yard collecting moss – much more than we needed.  We also found a small piece of bark with lichen growing on it.

As we arranged the plants inside the terrarium, I decided my son needed a lesson in garden design so that he wouldn’t crowd everything together. Later, I also read that we shouldn’t put too much moss into the terrarium so that the moss doesn’t overpower the small plants.

Once the terrarium is finished, you need to water it well, but after that, you only need to use a spray bottle once in a while to mist the plants and soil. Keep the lid open until the sides of the container have no more water droplets on them, and then shut it tight.

The terrarium needs to sit in a well-lit area, but no direct sunlight should fall on it.  Remember, these are shade plants.  Fertilizer isn’t needed either.  You don’t want the plants to grow too big, and when they start to get too big or the leaves touch the sides of the container, you’ll need to trim them.

After a few days, I noticed our plants looked a little brown and yellow, so I snipped off those leaves and hoped for the best.  Now, it’s looking good, and I’ve noticed some new growth on the wild, unidentified plant and the moss!

This was a fun, easy project, and it’s a perfect for children who enjoy planting or who are learning about plants.

Have you ever made a terrarium?