How To Make a Carnivorous Plant Terrarium

Terrestrial carnivorous plants--including Venus flytraps, sundews, pitcher plants, butterworts, and some bladderworts--are usually sold in sealed plastic cups. You can keep such plants in these closed cups for a limited time, but it's best to transfer them to a terrarium soon after you buy them. Terrariums range from modest 1-gallon fish bowls to much more expansive rectangular or polygonal aquarium-type containers of 100 gallons or more. Regardless of its size, your terrarium can provide the environment ideal for bog-loving carnivorous plants: high humidity coupled with a moist, acidic, and nutrient-poor substrate.

Here's what you'll need for your terrarium:

• A suitable tank that will not prove to be too small as its plants flower or grow taller.
• A safe and suitable tank cover that allows easy access and the retention of high humidity.
• A good light source: either direct sunlight for part of the day, or bright, broad-spectrum "grow lights." The latter is preferred because terrariums left in direct sunlight may experience dangerous overheating.
• The proper substrate materials: distilled water, clean gravel (avoid limestone and marble), long-fiber sphagnum moss, horticultural charcoal, and clean quartz sand. Note that you will use no potting soil, topsoil, or humus whatsoever.

TO SET UP YOUR TERRARIUM: First wash the tank and your materials to remove possible contaminants. Soak the sphagnum moss thoroughly in distilled water. Then place a one-inch-deep layer of gravel at the bottom. This will serve as the terrarium's drainage reservoir. On top of the gravel spread the equivalent of one-half inch of horticultural charcoal. Much of this will fall to the bottom of the tank--that's fine. Next, in a large bowl or basin combine the sphagnum moss with the sand, at a ratio of 1:1 by volume. Add one cup of charcoal to this mixture. Then apply the mixture as a three- to four-inch layer above the gravel and charcoal.

TO PLANT YOUR CARNIVORES: Make a hole in the substrate for each plant you have. The holes should be one inch deep by two inches wide. Carefully remove the plants from their cups and plug them--preexisting potting mixture and all--into the holes. Gently tamp the substrate around the plants so that there are no gaps below or around their roots.

FOR MORE ON HOW TO FEED YOUR PLANTS AND KEEP THEM HEALTHY: Ask for the Plant Care Sheets that describe the specific types of carnivorous plant you have.