Tam-Tam's Blog

Terrariums-The Basics Part Two
Dec 21, 2007 | 4:35 PM PST
Tags: terrariums , lighting , fluorescent , incandescent bulbs

Lighting:  

We know that foliage plants need between ten and twelve hours of light daily, and flowering vegetation needs about sixteen hours of light daily.  Deciding on what type of light source you will provide your terrarium is very important.  If you don't have an ideal place for your glass garden to receive the amount of light it needs, then you have two options.  Keep moving your terrarium around to optimize the natural lighting in your home or decide upon some artificial lighting assistance.   

Artificial lighting is the more practical solution.  Using fluorescent light fixtures with tubes that simulate sunlight and are designed for indoor gardening are a better choice than incandescent bulbs.  They cost less to use, they are cool burning, which means the plants will not get scorched, and they emit various rays that the plants need to grow well.   

Any fluorescent tube designed for indoor gardening will prove satisfactory.  Many glass gardeners have their favorites, one being Sylvania's Gro-Lux.  The Gro-Lux is considered to be one of the best all-around lights for seedling and houseplants because of its wide color distribution.  The price runs about $20.00 for a package of two tubes.  You may have to do a little research to figure out what would be the best type of lighting for your situation and product availability in your area, and of course you can always order on the internet.  

If you have plenty of windows with good light, you may opt for making one of the smaller terrariums to place there.  But for most people on their first try they usually decide on a small aquarium tank with its own light fixture.  If you happen to have a aquarium hood that has a incandescent light you have two options.  One- you can buy a new fluorescent light hood to fit the aquarium, or two- you can try one of the new screw in fluorescent bulbs designed to give an aquarium the benefits of fluorescent lighting.  They are called Mini Compact Fluorescent Bulbs.  They can run about $10.00 and have a long bulb life.  In fact, if you are using an aquarium tank the local pet store may be the first place to visit to find your fluorescent tubes/bulbs because they usually carry the tubes/bulbs for vivariums--(basically terrariums with critters).  

There are several types and sizes of fluorescent lighting fixtures and tubes.  Some are designed to hang, some stand on legs and others can be placed on top of the container.  Make sure to choose the best type and size fixture for your terrarium and location.  Before you buy your fixture, double check the system.   For instance, if you are going to use a hanging fixture, make sure it will not be difficult to hang and if it will detract from the room's appearance.  As always, make sure to follow all the directions and use the proper size tube for the fixture.  

 A good rule for fluorescent fixtures:  A fluorescent fixture should be placed a foot above the tops of foliage plants.  If the terrarium contains flowering vegetation, the fixture should be two or three inches lower. 
You will have to watch your plants to see if they are getting the right amount of light they need.  If the vegetation is spindly, which is a sign that it is reaching for light, lower the fixture.  On the other hand, if the leaves are turning slightly yellow, which is a sign of to much light, then raise the fixture.  

 One more note about incandescent bulbs:  These bulbs generate a great deal of heat, this is one reason why they are not recommended for terrarium illumination.  There are some incandescent bulbs that can be useful for the terrarium.  There is a floodlight type bulb called "plant spotlights".  These bulbs can be used to supplement natural light and to provide terrariums on a cool windowsill with heat in the wintertime. 

These floodlights can also be used to "spotlight" your terrarium to bring attention to it, or to accent a flowering or unusual plant.  The fixtures or "units" that are used with these plant floodlight bulbs can be fastened to a wall or set on the floor or a tall piece of furniture, or put on a shelf and decorative effects can be achieved.  If you choose to do this, after highlighting your glass garden, make sure to check the temperature near the terrarium.  If the temperature is rising due to the heat from the spotlight, make sure to move the unit farther away.