A terrarium is a great way to create your own little indoor oasis. Terrariums are created using clear plastic or glass containers such as fish bowls, aquariums, large glass jars or jugs. They can be open on the top or enclosed. Terrariums that are enclosed can recycle their water, need very little attention and are good for plants that thrive in high humidity. Open terrariums are better for plants that need a dryer climate, however, they need more frequent watering.
Plants growing in terrariums need indirect sunlight. Never place one in direct sunlight. Low growing, dense plants work well. You can also control the amount of growth by pruning. Select plants that have similar light and watering requirements, but choose variations in size, color and texture. Some plants that do well in terrariums include small ferns, carnivorous plants, polka dot plants, croton, creeping fig, Ti plant, ribbon plants and prayer plants. If an enclosed terrarium gets too moist and humid inside, open the lid for awhile.
When you start to set up your terrarium, the first thing you should add to the bottom of the container are small clay granules that you can find at most nurseries or garden centers. These are important for proper drainage and help keep the soil from becoming too soggy. (Unscented cat litter will work also.) Next add a thin layer of aquarium gravel. A layer of horticultural charcoal above the gravel will keep the soil from developing a sour odor. Then add a quality indoor potting soil, about 2 inches deep.
Now you are ready to add the plants you chose. Plant the taller ones in the back. Dig small holes for each plant and plant them no higher or lower than they were in the pot. You can add to the miniature landscape by adding rocks, shells, pieces of wood or small ceramic figurines like frogs, turtles, snails or even tiny fairies. Have fun creating your own little world.
The most important thing to remember with a terrarium is not to over water. Open terrariums need less water than other houseplants. Always water light. Closed terrariums only need to be watered every four to six months. Frequent pruning, pinching out tips will keep the plants from growing too tall.