How to Create a Thriving Closed Terrarium in a Mason Jar
Closed terrariums are miniature, self-contained indoor gardens that can thrive for years with minimal care. They’re a great way to bring a touch of nature indoors, and they can be easily customized to fit any space or style.
What You’ll Need
Equipment / Tools:
- Spray bottle or plant mister
Materials:
- Wide-mouthed Mason jar
- Small plants suitable for closed terrariums (see below for suggestions)
- Springtails or isopods (optional, for terrarium maintenance)
- Moss (optional, for moisture retention and visual appeal)
- Activated charcoal (optional, for odor absorption and water purification)
- Stones, shells, or other decorative objects (optional)
- Raffia ribbon (optional, for decoration)
Step-by-Step Instructions
1. Clean the Jar
Thoroughly wash the Mason jar with mild, non-toxic soap and water, especially if it has been previously cleaned with harsh chemicals. Allow it to air dry completely.
2. Create the Substrate Layer
The substrate layer provides drainage and support for your terrarium plants. It should consist of a combination of soil, sand, and/or moss. Place a layer of sand at the bottom for drainage, followed by a layer of potting soil. You can also add a layer of moss on top of the soil to help retain moisture and keep the terrarium cleaner.
3. Moisten the Soil
Dampen the potting soil of your plants before removing them from their pots or cells. Gently squeeze the sides of the container and tip the plant into your hand, taking care not to pull it out by the top.
4. Plant the Terrarium
Place the plants over the substrate layer, ensuring that the root ball is compact and covered with soil. Press the root ball into the soil so that it is mounded but does not overflow.
5. Arrange the Plants
Arrange the plants within the terrarium to allow for good visibility and an attractive aesthetic. Taller plants can be placed in the center of a round jar for a visually appealing effect.
Tip: Regularly clean the inside of the jar as you work to make the final cleaning process easier. Use a soft cotton cloth, as paper towels may leave fibers on the glass.
6. Add Moss (Optional)
For a finishing touch, press small pieces of moss onto the soil around the plants, creating a green mound. Keep the moss away from the crown of the plants.
7. Decorate Your Terrarium (Optional)
Add decorative elements such as stones, shells, miniature figurines, or other objects that can withstand the humid environment of a terrarium. You can also create memory terrariums by incorporating keepsakes from vacations or special occasions.
8. Care for Your Terrarium
- Light: Keep your terrarium out of direct sunlight but provide it with bright, indirect light.
- Watering: Closed terrariums generally do not require watering for several months. However, check the soil every few weeks and water sparingly if it feels dry.
- Condensation: If you notice excessive condensation on the jar, leave it open for a few hours to allow the soil to dry out slightly.
- Misting: Open jar terrariums require more moisture and should be misted regularly, at least once a week.
Choosing Plants for a Closed Terrarium
Select plants that thrive in moist environments and are not susceptible to mildew or fungus. Some suitable options include:
- African Violets
- Maidenhair Ferns
- Baby Tears
- Polka Dot Plant
- Nerve Plant
- Polka Dot Begonia
- Spike Moss
- Golden Pothos
Troubleshooting Common Issues
Fungus or Mildew: If you notice fungus or mildew in your terrarium, remove the affected plants and treat the terrarium with a fungicide. Ensure that there is adequate ventilation to prevent future outbreaks.
Excess Moisture: If the soil in your terrarium is consistently wet, open the lid for a few hours to allow it to dry out. Overwatering can lead to root rot and other problems.
Lack of Sunlight: If your terrarium plants are not receiving enough light, move it to a brighter location with indirect light. Insufficient light can stunt growth and cause plants to become leggy.
By following these tips, you can create a thriving closed terrarium that will bring beauty and tranquility to your home for years to come.
