We deliver and sell lots of terrariums at our plant store in Marshfield, MO. Our horticulturist, Dave, is a true artist when it comes to designing them for beauty and longevity. He’s put this list of terrarium tips together so you can keep yours healthy!
First of all, there are several ways to create terrariums. Closed terrariums have a lid and no vent holes. Open terrariums may have an opening at the front or top, or vent holes. Both closed and open terrariums are fun to own, but there’s a difference in watering and sunlight needs for each.
When Dave selects plants for our terrariums, he chooses either tropical plants (which like to be moist) or succulents/cacti (which prefer a dryer climate) to put in each one. Your plants will make a huge difference in terrarium care needs as well.
Read on…by the end you’ll know how to keep your terrarium alive!
How to Care for Terrariums with Tropical Plants
Tropical Terrarium Watering
Add water to leafy plants as needed to retain moisture. Don’t let the soil dry out, but ensure that there’s no sitting water inside.
How often should I mist moss in a terrarium?
Besides keeping soil moist, it’s best to make sure the top of your moss is moist as well. Mist moss once a week, or if it starts to look dry.
Can I use tap water in a terrarium?
Use distilled water, drinking water, or rainwater in your terrarium. Well and city water will leave lime deposits on the glass and plant leaves, making them unsightly and hard to clean.
Do I have to water a closed terrarium?
In a truly closed terrarium, you won’t need to water at all, but most lose a little water to evaporation over time. Once the soil becomes dry, open it up and mist inside.
Tropical Terrarium Lighting
It is important that these tropical plants and moss receive good lighting to properly grow.
- Bright indirect light from a window is ideal (direct sunlight will create too much heat and become too intense). This just means you shouldn’t sit it in the sun’s rays. Keep it away from windows, but in a bright room.
- Artificial light in close proximity (grow light or regular lamp) works great, too.
Depending on the light source, the terrarium may need to be rotated once a week to provide maximum lighting to the entire landscape.
How much sunlight does a closed terrarium need?
Since closed terrariums don’t allow heat to escape through a vent, be more mindful of placing them in the sun. If they heat to too high a temperature, the plants inside will die.
Tropical Terrarium Fertilizer
Due to the confined space, rapid growth is not encouraged. If you purchased your terrarium at Grass Roots, a slow-release fertilizer has already been applied to provide the necessary nutrients for the next 4 months. If you designed one yourself or purchased it elsewhere, apply a diluted indoor plant fertilizer or Osmocote slow release once per month.
How to Care for Terrariums with Succulents & Cacti
Can you put succulents in a closed terrarium?
We don’t recommend adding succulents or cacti to a closed terrarium. This is because a closed terrarium becomes its own ecosystem as water condenses onto the top like a cloud, then rains or stays humid…mimicking a rainforest. That’s why tropic plants do so well in closed terrariums. This climate is not a succulent’s natural habitat, so they won’t last long in a closed terrarium.
Succulent Terrarium Watering
Succulents need very little water, and even less so in a terrarium. Use distilled, drinking, or rainwater and water once a month. You may also use a nickel to quarter size ice cube to slowly water in – this makes it easier and cleaner to work with.
Succulent Terrarium Lighting
Provide bright and indirect light to succulents and cacti. These plants need 8 hours of good lighting. This can be achieved by using a sheer curtain on a bright window, or placing the terrarium far enough from the window to create a faint undefined shadow. You can also use a regular lamp or a grow light.
Succulent Terrarium Fertilizer
Succulents like a low analysis fertilizer (2-7-7) applied once to twice a month during regular waterings.
Succulent Terrarium Filtration
Layer your terrarium to provide the best environment for the plants. Not only does this aid in proper drainage, moisture retention, and good air circulation, but reduces potential mold and fungus. These layers include rock, activated charcoal, organic sphagnum peat moss and premium potting mix.