Building and Caring for a Terrarium is an Easy Project for Kids
Building and caring for a Terrarium – miniature garden enclosed in clear glass or plastic is an easy project for young gardeners. A covered, well-constructed terrarium needs little care, only requiring warmth and low light to flourish. Plus, a terrarium is a great way to demonstrate how water transpires from plants and evaporates from soil to create rain that falls back to the soil, and is then drawn up through the plant roots and lost through transpiration again.
1. Choosing a Container
Select any clear or lightly tinted glass or plastic container with an opening big enough for your child’s hand to easily fit through. A fish tank, large brandy snifter, two-liter pickle jar, candy jar, and even a casserole dish are all good choices. If the container doesn’t have a lid, you can cover it with a sheet of clear plastic once the terrarium is planted. Wash the container with a 10:1 solution of bleach and water to avoid bacteria, fungi, and algae that thrive on soil surfaces in warm, moist environments.
2. Selecting Plants
Choose naturally small or slow-growing plants that grow well in moist environments, picking plants with similar requirements for temperature, light, and humidity. Add interest by choosing plants that provide a variety of height, texture, leaf size, and color.
To create a woodland effect, gather mosses, lichens, small ferns, pinecones, small stones, and bits of wood from a nearby forest. You can also look for small plants such as these:
- Maidenhair fern (Adiantum spp.)
- Pussytoes (Antennaria spp.)
- Wild strawberry (Fragaria spp)
- Patridgeberry (Mitchella repens)
- Foamflower (Tiarella cordifolia)
- Spiderwort (Tradescantia virginiana)
- Sweet violet (Viola odorata)
- Dwarf Goatsbeard (Aruncus aethusifolius)
- Sweet Woodruff (Asperula odorata)
- Ebony spleenwort fern (Asplenium platyneuron)
- Bunchberry (Cornus canadensis)
- Herb Robert (Geranium robertianum)
- Corsican mint (Mentha requienii)
- Labrador violet (Viola labradorica)
Many houseplants native to tropical environments also grow well in a terrarium. Check out these ideas:
- Asparagus fern (Asparagus setaceus)
- Fluffy ruffles fern (Nephrolephis exaltata)
- Peperomia (Peperomia caperata)
- Aluminum plant (Pilea cadierei minima)
- Artillery Plant (Pilea microphylla)
- Baby’s tears (Soleirolia Soleirolii)
- Cypress Spikemoss (Selaginella plana)
3. Building the Layers
Begin by creating a drainage area of pebbles and charcoal by covering the bottom of the container with one to two centimeters of sand or pea gravel; this helps keep excess water at the bottom of the terrarium. Next, carefully add a seven-millimeter-deep layer of crushed charcoal to absorb unpleasant odors.
To keep soil out of the drainage area, cover the pebbles and charcoal with a piece of synthetic fabric. Recycled nylon fabric, say from stockings or a curtain remnant, is ideal because nylon cloth will contain the soil but allow water to pass through, plus it’ll decompose slowly. Place eight to ten centimeters of sterile, slightly damp potting soil over the nylon. Using a spoon, level the soil or mold it into contours and valleys.
4. Planting the Terrarium
Place the largest specimen near the center if you plan to view the terrarium from all sides, but plant the tallest in the background if you plan to view the terrarium from only two or three sides. Making sure no leaves will touch the sides of the container, which may cause them to turn brown, place each plant in a small hole and gently firm the soil around its roots. Just for fun, you can also add a small figurine or two.
If the glass is dirty, spray it lightly with water and wipe it with a piece of cotton wrapped around the handle of a wooden spoon. Cover the terrarium and place in a bright area, but not in direct sunlight, such as in a north- or northeast-facing window. Direct sunlight can burn plant leaves.
5. Caring for the Terrarium
Check the terrarium daily for a week. If water condenses heavily on the inside glass, remove the lid to let excess moisture evaporate. If the plant’s wilt, and no condensation forms, add a little water. After that, water only when the soil feels dry. Don’t fertilize unless the plants start to turn yellow, and then only at one-fourth the recommended rate. When the plants are as tall as you want them, pinch off any new growth. This will also encourage them to grow bushier. Remove any faded flowers to prevent disease. Once a year, add nutrients and freshen the terrarium’s appearance by scraping off the top layer and adding more potting soil.