Wintertime can be somewhat depressing. We get up in the dark, go to work from 8 a.m. to 5 p.m. and then turn around and come home in the dark. If you're lucky, you might get a chance to steal away a few hours in the sun over the weekend to take care of outdoor chores. But if you're like I am, its much easier to be happy when you have something new growing.
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If you own a greenhouse, the opportunities are limitless, but what about the rest of us. Do you have an old fish tank, a cider jug or any other transparent glass or plastic container? If so, you're well on your way to gardening in a terrarium. Terrariums are like mini-greenhouses; they can be used to start transplants, or even to grow a miniature landscape. The true terrarium is tightly closed, but as long as it's clear, almost any type of container may be used.
Many plants are suitable for growing in terrariums. However, plants that don't need a lot of light, and have a low, dense growth habit are usually preferred. Plants like begonia, creeping fig, club moss, English ivy, pothos, pink polka dot, philodendron, Irish moss, spider plant, and Venus fly trap will all grow well inside a terrarium.
Most terrarium plants have a medium light requirement. These plants will grow best when the terrarium is located within several feet of a bright window, but not in direct sun.
Soil for terrariums must be high in organic matter, clean and well-drained. Sterile growing media that are high in peat moss and pine bark work well. These soilless growing media are available at most any garden center.
If you're wondering how people plant a terrarium, it's really quite simple. In general, the bottom quarter of the container will be filled with pea gravel or aquarium gravel for drainage. Next, a 12 inch layer of horticultural charcoal is placed above the pebbles to prevent the soil from developing a sour smell. Then dry soil is added to a depth of at least 112 inches. Rocks and wood are the last addition before planting.
When it comes to planting, plants should be placed so that the top of the root ball is level with the top of the soil. If you're having trouble planting a container with a small opening, try digging holes with a pointed stick and use slender tongs or a stick with a wire loop on the end to place plants. After a plant has been placed in the hole simply fill in and firm the soil gently using a long stick with a cork on the end.
After planting, mist to clean soil sticking to leaves or the sides of the container. The water from the mist should be sufficient to settle the soil and provide moisture. Mist again the next day. The water level at the bottom should not exceed a quarter inch. Keep the container uncovered until the leaves completely dry, then apply the cover if you have one.
The closed terrarium probably will not need to be watered for four to six months. Open terrariums need occasional watering, but not as often as other house plants. However, waterings should always be light.
Even in these the darkest days of winter, the greenery of plants growing in a terrarium can bring a ray of springtime cheer.