Once you decide to make a terrarium yourself, you are probably asking: what is the difference between open vs. closed terrariums? This post will help you learn about advantages and disadvantages of both open and closed terrariums. I will also discuss which plants are better for open and closed terrariums.
What is an open terrarium?
Open terrariums are the ones which have plants in open containers – ones which have no lid. As they are open, you can easily access the plants.
Advantages of open terrariums:
- One of the main advantages of open terrariums is that plants can always get fresh air from the environment
- You have an easy access to plants for watering, pruning and changing the design
- Terrarium can be ventilated to prevent too much condensation.
Disadvantages of open terrariums:
- Because of constant air supply, terrarium plants can grow faster
- Terrarium design can be damaged easily, as there is no lid covering the plants.
The best plants for open terrariums are succulents, which normally survive in dry air conditions. You should not grow plants which are used to warm and humid conditions, as they will not tolerate cold air coming from outside. Example of succulent plants for miniature open terrariums are dwarf aloe, gasteria, dwarf jade plant, sedum, aeonium and others.
How to care for open terrariums? General tips.
Make sure to water your plants with clean water. I would recommend watering your plants with bottled water as most plants can be affected by polluted water, which is also full of chemicals and chlorine. Make sure to never overwater, and to avoid this try misting or giving water with a syringe.
What is more, don’t forget to prune your plants when they become too leggy and come out of the terrarium space.
Fertilizing is not too important, but you should give your plants some plant food if they become weak. You can also fertilize plants which need to consume insects to get nutrients (carnivorous plants). Of course, you should provide them with fertilizer if you don’t have any bugs to throw in for their dinner!
What is a closed terrarium?
Enclosed terrariums are usually jars and other containers that have a lid. Sealable terrariums look fascinating but often require additional maintenance. Let’s look at pros and cons of closed terrariums.
Advantages of closed terrariums:
- Pruning and trimming is needed less frequently, than in open terrariums
- You need to water it less frequently
- Because there is less air coming in (only when you open the lid for ventilation), the growth of plants is slower.
Disadvantages of closed terrariums:
- It requires regular ventilation, otherwise condensation builds up on the glass
- The drainage layer may become full of water and gases from material decomposition
- Double bottom drainage layer is often required for absorbing unwanted water and for providing substrate with oxygen.
Closed terrariums best suit tropical plants that require warm weather and humidity. Closed lid will provide with condensation (humidity) and building of up heat inside the enclosed container and from the sunlight or artificial lighting. The best plants for enclosed terrariums are tropical cactuses, mosses, ferns and others.
How to care for your closed terrarium. General tips
To care for your closed terrarium, make sure to hide it from direct sunlight. If your terrarium gets too much light, the heat starts to build up inside and has no way out for long periods of time. This causes very high temperatures in terrariums, which also burn your plants.
To avoid overwatering a closed terrarium, start observing the inside glass for condensation. Condensation in closed terrariums is normal, but too many water drops on the glass mean that you should open the lid for 30 minutes to 1 hour to let the air out.
One tip…
I would highly recommend not to mix plants with different requirements in one terrarium. Make sure to find the name of your plant and read about it.
Conditions include temperature, sun exposure, humidity levels, drainage systems and you should consider these factors before placing plants together. Even though it is possible to do so, I would not recommend this to terrarium beginners. Also, placing humidity-loving plants in open terrariums is also possible, but they will require more care.