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With outdoor gardening limited, try terrariums

Even if you don't have access to a large area of land, that doesn't mean you can't garden. The answer lies in terrariums: miniature plants in proportionately small containers. A terrarium can be one living plant growing and thriving inside a glass container. It can also be an entire landscape, a desert, woodland, tropical jungle or gardener's fantasy. Imagine creating a complete garden you can set on your coffee table.

The terrarium was originally invented as a way of transporting living plants from far parts of the world when voyages took months or longer. Today's terrariums tend to be more decorative in nature. But like their predecessors, they provide a low-maintenance garden requiring little time and attention once planted. A few basics will get you started.

Containers: Start with the container and then choose suitable plant materials. The choice of a container is mainly a matter of space and preference. Essentially any clear glass container that readily opens and closes will serve as a terrarium. Anything from a crystal brandy snifter to a jam jar is suitable.

The most important limitation is the color of the glass. Clear glass transmits all available light. Colored containers reduce light intensity and tend to transmit their own color while absorbing all other colors. For optimum plant growth, choose a container of clear glass.

Plexiglas or Lucite are viable alternatives to glass. They are lighter and less fragile, but scratch easily, so use care during handling and cleaning.

Plants: Light is the first thing you must consider before choosing plants. Be aware of the specific light requirements of your terrarium plants.

Growing temperature requirements also vary among plants. Look closely at the environment your plants will occupy before purchasing them. Tissue damage occurs if the temperature drops below the recommended minimum. Warm-temperature plants require a growing temperature of 65 to 90 degrees. Intermediate-temperature plants will thrive within a range of 50 to 70 degrees. Cool-temperature plants must be grown in 35 to 65 degrees, certainly not suitable for indoors.

Soil: Because terrariums have no drainage holes, a well-textured soil mix must be porous enough for good water drainage as well as air exchange.

For each terrarium, choose plants that require the same soil mix, then purchase a commercially prepared terrarium soil mix. If the soil appears to be too dense, too rich or too moisture-retentive, add vermiculite or perlite. If you are planting a desert scene using cacti and other succulents, add a little extra sand or grit (fine gravel) to the mix.

The soil must rest on a layer of drainage material from one-half to 2 inches deep, depending on the size of the terrarium. Mix three parts gravel to one part charcoal (purchased in pet or garden stores) to catch excess water. The gravel size should be proportionate to the terrarium size.

You will need a soil separator to prevent soil from washing into the drainage area. Place the separator material in a thin layer between the soil and gravel. Screen material, nylon netting or an old nylon stocking make good separators.

Planting: First, clean the container. It will be difficult to clean after planting. Rinse the charcoal so its fine dust won't coat the terrarium. Mix the charcoal with the drainage material. Distribute it evenly across the bottom of the terrarium. Cover drainage material with a soil separator.

Dampen the soil, then place it in the terrarium, distributing it evenly over the soil separator, or banking and mounding as you wish. As you work, keep the sides of the glass clean, wiping off smudges as you go.

Before removing plants from their pots, arrange them outside the container. Now make impressions in the soil where each plant will be placed. Remove plants from pots and brush away excess soil. Insert plants in the terrarium and tamp down soil over root balls. If you are adding decorative pieces, do that now. Water evenly and slowly. Do not overwater! Mist foliage and place in suitable light.

If you are using a narrow-necked container for your terrarium, you will have to fashion a few tools. Chopsticks or knitting needles with a small spoon taped on the end will help dig the holes and tamp down the soil. When pruning becomes necessary, tape a razor blade to the end.

Maintenance: Your terrarium will require some maintenance, but much less than a potted plant collection. Turn the terrarium around periodically so the plants don't lean in the direction of the light source. If you've created a closed terrarium, remove the cover frequently for ventilation. Check weekly for soil moisture; do not let the terrarium dry out. For a small container, a mister is good for light watering. Water lightly and evenly over the entire soil surface.

With optimal growing conditions in your terrarium, the fertilizer requirements will be less than with potted plants. Use a liquid fertilizer diluted to one-quarter of the manufacturer's instructions. If your terrarium becomes infested with insects, you must act quickly. A systemic pesticide is best.

Groom the terrarium periodically. This means removing dead or decaying vegetation as soon as you notice it. Also, trim, remove or replace rampantly growing plants.

Terrariums are not only lovely, but also have interesting practical aspects. Use them for children's projects or as a place to germinate and grow seedlings. Make up a terrarium kit, and give it to a new or sick friend. Now that you have become an expert, terrarium landscapes are only limited by your imagination.

With outdoor gardening limited, try terrariums 01/28/10 [Last modified: Monday, November 7, 2011 5:54pm]
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