DIY Terrarium Tutorial and FAQs

If you have an open terrarium, water it about once a week, or when the soil feels dry. Add just enough water to evenly moisten the soil—stop if water starts to pool at the bottom. If your plants have become large and the plant roots have reached the bottom of your terrarium, you may water more heavily until water saturates the soil, moss and charcoal layers. If you have a closed terrarium, you will likely only need to water it a few times a year. Evenly add about 1 oz of water when condensation disappears, soil dries or leaves begin to crisp. Repeat daily, if necessary, until light condensation returns and soil is evenly and lightly damp. Always keep the lid closed except briefly for trimming or cleaning. It is always best to err on the side of underwatering with terrariums due to the difficulty of removing excess water compared to simply adding more water.

Leaves that are turning black and “mushy”, soil that appears heavily saturated or large water droplets over the entire inside glass that never dissipate is a sign that there is too much condensation built up in your terrarium. Remove the lid for approximately 2 hours, ensuring the soil does not dry out during this time. Place the lid back on your terrarium. If needed, repeat this daily until condensation forms a light mist instead of heavy droplets and the soil dries slightly. If you have an open terrarium and the plants are showing signs of overwatering, place it near a fan or open window (away from direct sunlight) to provide airflow to slightly dry the soil, set it on a heat mat and/or use a pipette to suction out excess water that has collected at the bottom of your terrarium. Note that at times terrariums may show heavy water droplets that dissipate within a day to form a light mist. This is normal and may be due to slight changes in temperature or atmospheric pressure. Monitor plant health daily.

Keep your terrarium out of direct sunlight. The glass can magnify heat and scorch plants. Ideally, provide your terrarium with bright to medium indirect light daily for approximately eight to twelve hours. A grow light or bright lamp is sufficient.

After loosening the root ball, gently and loosely bunch roots together to make it easier to place in the hole. It is important not to tightly compact the roots as this can lead to root suffocation. You can also choose to trim the roots with a clean pair of scissors.

This is common in new terrariums, normally harmless and may indicate a healthy environment. Mycelium, for example, is beneficial. Monitor overall health. Remove unwanted or overgrown fungus. Sometimes these fungal structures dissipate on their own as terrariums age. If you notice the soil is heavily saturated, water is pooled at the bottom of your terrarium and the "mold" is spreading quickly, this may be due to overwatering which causes too much condensation buildup. Immediately remove the fungal structures by hand or with tweezers and follow the steps noted in the overwatering section.

Trimming plants is optional and depends on the desired appearance of your terrarium. If you have a closed terrarium, you may notice that the plant leaves are touching the glass. This is normal and typically does not cause any harm to the plants due to their acclimatization to a 100% humid environment. You may trim your plants to give it a more manicured appearance and encourage branching. Just be sure to promptly replace the lid. With many plant varieties, trimming encourages new growth and branching to create a fuller, more compact appearance.

Yes. You can definitely change the type of terrarium you have after it has been assembled. Be sure to do this only once your terrarium plants are established and show signs of new growth. You want your plants to be strong so they can easily acclimate to a change in humidity level. If you have a closed terrarium and would like to change it to an open terrarium, remove the lid for two hours and then replace the lid. Repeat this daily, for seven days, increasing the time the lid is off by one hour per day (i.e. lid off for three hours on day two, four hours on day three, etc). Immediately replace the lid if you notice that the plant leaves begin to wilt or show signs of distress. Keep the lid closed until the leaves begin to perk up and show signs of recovery at which time you may continue the acclimation process. If the soil lightly dries out and your plants appear healthy during this process, you may water your terrarium and permanently remove the lid. This is a sign that the acclimation process has completed. Sometimes it is unavoidable to lose leaves during this process but, if the main plant, stem and roots remain healthy, your plants should recover. If you have an open terrarium and would like to change it to a closed terrarium, follow the steps above, but instead of removing a lid, cover your terrarium with a lid. Before you start the process, ensure that the open terrarium soil is very lightly damp and not heavily watered. You will know when the process is complete when there is a light mist on the interior glass, leaves are not black/mushy and the soil is evenly damp.

Plants in closed terrariums are able to survive with minimal to no watering and without the need for constant airflow by converting carbon dioxide into oxygen during the day and using this oxygen to release carbon dioxide at night. This cycle repeats indefinitely creating a self-sustaining environment.