Guest Author - Wendy Lee

When building your own terrarium, start out by selecting your container, small aquariums, brandy glasses, and for the more advanced growers, bottles. Keep in mind, the larger the opening of your container, the more frequent watering it will need. Also, think of a front and a back for your terrarium and build your layers of gravel and soil as such. If your container is large enough, as with a giant brandy glass, consider having a hill in the center to allow for more surface area to plant in. In general, any open glass or clear plastic container will do well for a terrarium.

When adding layers of gravel, charcoal, and soil use them in a dry state to keep them from sticking to the sides of your container and minimize interior cleanup.

The most important thing in keeping a terrarium, as with all other houseplants is to provide adequate drainage. In building your own terrarium this can be achieved by laying down an initial layer of sand or pebble gravel. As a secondary layer to prevent odors from decomposing leaf litter, activated charcoal is used. This is the same material that can be found in the filter for a fish aquarium.

On top of these two layers a type of moss will be needed in order to prevent soil from intermingling and thus making your previous work pointless. Sphagnum moss, sometimes known in flower shops as sheet moss, is best for this layer. The moss will also aide in increasing the amount of time between waterings and the humidity in your terrarium due to its water holding properties. For ease of stretching out the moss to make a thin layer, soak it in warm water for 10 – 15 minutes as in its dry state the moss is extremely brittle.

Soil is the final layer before planting. There are specific terrarium mixes commercially available, however, regular potting mix will be suitable after adding 1 part sand to 3 parts potting medium. Never use sand from the beach is it contains not only vast amounts of organisms, but trace amounts of salt as well which will leach into the soil and burn your plants. Adding fertilizer to the soil is entirely not necessary as slow growing plants are desired for keeping the terrarium looking good for years.

In selecting plants for your terrarium, think of slow growing species. Ferns are very popular for terrariums, due to this very fact and that they enjoy humidity. Other plants to think of are English Ivy, Swedish Ivy, Pothos, Miniature Begonia, Peperomias, African Violets, Prayer Plant, Bird’s Nest Sansevieria (also called Bird’s Nest Fern), Parlor Palm, Creeping Fig, Spider Plant, Podocarpus, Nerve Plant and Partridge Berry.

Choose plants for your terrarium that have similar light, water, and humidity needs. For interest take into account the texture, color, and size of your plants when creating your miniature landscape under glass. When planting them be sure to check for any signs of disease or infestation, as the prime conditions of a terrarium can hasten their effects. Remove dead or dying leaves, as well as anything else objectionable.

Once the landscaping for your terrarium has been figured out, decorations such as drift wood, rocks, seashells, or other items that suit your fancy can be added. Be sure to wash these items in hot soapy water and to rinse them well to reduce the risk of introducing fungus or insects to your terrarium. Good Luck!