By: Tommy Adams, Chelsea Connor, Amber Epps, and David Lanier
The purpose of this Instructable is to show how to make a terrarium out of an incandescent light bulb.
If you are using a flood light bulb, be aware that these contain mercury and extra precaution should be taken.
15-25 minutesTotal Cost:
$8.00 - $10.00 when purchasing all materials.
Step 1: Frequently Asked Questions
What is a terrarium?
Light bulb terrariums are miniature earth enclosure ecosystems that are self-sufficient and require minimal care. (See Image #1 "Terrarium Basics" for more information).
Who invented terrariums?
Terrariums were first discovered by a London botanist, Dr. Nathaniel Ward, in 1827. At that time, the London streets were filled with air pollution that threatened to kill the plants in his garden. In an attempt to protect his plants, he put them in a closed glass jar filled with dirt, and soon Dr. Ward observed a small healthy fern growing! Since that day, he built miniature fern cases to protect his plants, which we now call terrariums. (Source:
How do they work?
Plants releases water vapor which condenses on the glass in the form of water droplets. As gravity pulls them down, they re-hydrate the soil. As the roots take up the water, the soil and micro-bacteria release carbon dioxide, which the plants re-absorbs. (See Image #2 "How Terrariums Work" to see a diagram).
What plants should I use?
Choose small plants that will fit inside your light bulb as well as plants that are humidity tolerant. Recommendations: Sphagnum, Moss Baby's Tears or Angel's Tears, Pearlwort, African Violet, Creeping Fig.
Can I have animals in a terrarium?*
Unfortunately, it is not as simple as adding your favorite animal to your terrarium. Different animals require different types of terrariums. Be sure to DO YOUR RESEARCH before deciding on adding animals! We recommend Firefly Encyclopedia of the Vivarium by David Alderton, which gives a comprehensive overview of keeping amphibians, reptiles, and insects in terrariums for beginners. It is easy to read and understand. Attention to your animal's needs is essential.
*DO NOT use animals for this project. Light bulbs are too small for animals to live inside!
Step 2: Prepare Your Work Area
You will need: newspaper or cloth, gloves, and safety eye wear. Have all other materials nearby.
Step 3: Disassemble Your Light Bulb
You will need: needle nose pliers, wire cutters (or regular pliers), tweezers, sponge, salt, cotton swab, water and a flat head screwdriver. This step is one of the most difficult steps, but you should not give up. With some patience and guidance we know that you will be able to successfully disassemble the light bulb.
NOTE: Here's the link to watch the video if you are using the Instructables app.
Step 4: Clear Your Light Bulb
You will need: salt or sugar, sponge, cotton swab/ paint brush, and water.
Step 5: Add Small Rocks
You will need: small rocks or pebbles.
Step 6: Add Activated Charcoal
You will need: activated charcoal.
(REMINDER: Charcoal is important because it helps remove toxins from the soil and keeps the soil fresh.)
Step 7: Add Soil
You will need: soil, and a funnel.
Step 8: Add Your Plant
You will need: small terrarium plant, and a screwdriver.
Step 9: Clean Your Light Bulb
You will need: cotton swab or paint brush.
Step 10: Add Water
You will need: light bulb terrarium, and water.
Step 11: Install Cork
You will need: light bulb terrarium, and a cork.
Step 12: Display and Enjoy!
Above are two different methods of displaying your terrarium.
Small ring stand
These are only two of the many display options available. Don't be afraid to get creative with your display. Thank you for reading! We hope you enjoy your new light bulb terrarium. They make great gifts and decorative items!