What is a Terrarium?
The word Terrarium can be divided in two parts, namely “Terra” which is a Latin word meaning Earth and “rium” which is derived from “Aquarium” meaning in a transparent container. Thus as the two words together mean “Earth in a transparent container”, a Terrarium is the art of creating an ecosystem with plants inside an open or closed transparent container. Along with the plants one can also add some other elements like wood and rocks in order to give it the look of a natural landscape.
The first Terrarium was accidentally developed in 1842 by famous botanist Nathaniel Bagshaw Ward. He used to have closed jars with different insects for observing their behaviour and accidentally left one of them unattended. A fern spore in the jar grew and germinated into a plant. This jar became the first terrarium. The trend quickly spread in the Victorian Era amongst the English. Instead of the word terrarium, it was initially known as the Wardian case.
The modern Terrarium can either be open or closed depending on the type of plants intended to be grown in it. Plants which require humid conditions are used in closed terrariums whereas plants which require dry conditions are used in open terrariums.
Now that we know what a terrarium is, let’s dive a little deeper and see what goes into making one.
The first thing you must do before making a terrarium, is to decide the plants you want to
grow in it. As different plants have different requirements, it is important to pick plants with similar needs and requirements so that it’s easier to maintain them under a single maintenance regime. Plants with varied needs in one container would mean disaster as each plant would require separate attention depending on their requirements, making it really hard to take care of the Terrarium.
Hence it is good to do thorough research about your plants before planning to make a terrarium.
The key requirements to find out about a plant are Light, Watering, Substrate, Temperature and Humidity.
The first thing to be considered whilst choosing a container for a terrarium is the type
of plants to be grown in it. Some plants like Ferns, Fittonias and other tropical plants, prefer humid conditions and hence should only be used in closed containers so that the conditions of a rainforest can be mimicked, making it ideal for the plants. On the other hand Succulents and Cactus prefer dry conditions, so an open container is ideal for growing such plants.
Another crucial thing to be considered is the size of the container. Depending on the selection of plants the container should be big enough. The size of the full grown plants should be kept in mind as one wouldn’t want the plants to outgrow the container.
As a terrarium also adds to the décor of a place, one could also choose containers of various shapes and sizes but keeping in mind the above two crucial points.
This is a really important point of discussion as the growth of your plants depends a lot
on the substrate and hence it is very important to get it right. The main thing to be considered while choosing the type of substrate is the type of plants you want to grow. Different types of plants have different requirements in regards to the substrate. Some plants require a well-drained substrate whereas some plants require a dry sandy substrate. I prefer using just Coco peat as the substrate for plants which require humid conditions. As I am also into Aquascaping and Nature Aquariums, I tend to use a lot of aquatic plants which are grown immersed. Most of these plants are marginal plants, which grow near water bodies and during the monsoon season the water level rises causing them to be submerged under water. Thus they can adapt to both immersed and submersed conditions.
Over the years I have observed that Coco Peat is the most suitable substrate for these plants as it has a high water retention capacity as well as being a lose well drained substrate, making it ideal for plants requiring high humid conditions. For other plants such as Ferns, Begonias etc., a mix of potting soil and Coco Peat would be ideal.
For succulents and cactus, a dry sandy substrate is required. The ideal substrate mix for these plants is a mixture of potting soil, coarse sand and perlite or pumice stones (ADA Power-Sand). I prefer a 3:2:1 ratio of the above respectively.
After figuring out the kind of substrate you need, you will need to make a drainage layer above which you can put the substrate. The drainage layer is crucial for plants which require high humidity and a moist substrate. Though such plants require a moist substrate, you don’t want the roots of the plants to be sitting in water, causing root rot. The water trickles through the substrate and accumulates in the drainage layer which then slowly evaporates causing the humidity to come up through the substrate. There are a variety of options for a good drainage layer, like Pea Gravel, Clay Balls, Lava Rocks etc. I prefer using ADA’s Power-sand, which are small Pumice Stones. As it is highly porous, it is good at absorbing the water, therefore increasing the overall water retention capacity of the substrate.
For Succulents and Cactus, a drainage layer is not required as these plants don’t require frequent watering.
This is another crucial point for every terrarium as different plants have different light
requirements. If you want to place the terrarium in Sunlight, you must make sure that the amount of sunlight the concerned spot receives is ideal for the plants. Plants like Ferns and Orchids require indirect sunlight or partial shade depending on the species. Therefore it is very important to do your research before buying your plants and choosing the spot where you intend to keep the terrarium.
If you plan to keep it indoors, you will need a good LED light with a colour temperature of 6500K.
The photoperiod, which is the duration of light, should be between 8-10 hrs.
How do I maintain my Terrariums?
For Tropical and Aquatic plants (emmersed), I prefer using a good foliar spray.
Currently I like using the DOOA Wabi Kusa Mist, which is an excellent foliar spray with some pest repellent qualities as well. Unlike a pot where you can frequently add Manure or Compost depending of the needs of the plant, it isn’t easy to do so in a terrarium as it would mean breaking the terrarium apart considering how delicate the scape/setup is. You may ask why we can’t use liquid fertilizers. Liquid fertilizers should ideally be absorbed by the soil and the excess should be washed off with water. This is possible in a regular pot as it has holes at the bottom for the water to drain out but even though terrariums have a drainage layer, there is no way for the water to completely drain out from the container, hence causing the substrate to get saturated with the fertilizer leading to an overdose of it. After experimenting for years I finally found peace in Foliar Sprays (no one likes to see their plants wilt :p)
2. Mould treatment:
One of the biggest problems in a new terrarium is mould infestation. Mould is a fungus that can occur in closed terrariums when there isn’t enough aeration. It looks like a white stringy substance which may cover the substrate and the plants. As a preventive measure it is good
to leave your terrarium open for 15 -20 minutes every time your water it. This allows fresh air to enter the container, helping in proper aeration. In case your terrarium is already infected with mould, spray some Neem oil mixed with water on the affected areas. According to my experience this is the best solution to the mould problem.
This completely depends on the plants in your terrarium. It is advised to find out the
water requirements of your plants and follow it as closely as possible.
A sign of a healthy terrarium is good growth. In order to promote such growth it is very
important to keep trimming the plants once they grow big. It is also important to cut off dried and dead leaves so that new leaves can come out.
To understand more about Terrariums I would encourage readers to try their hand at making one first. It is a therapeutic hobby which not only helps relieve stress but also helps you understand nature more intricately.
A terrarium can also be an interesting addition to your home décor, adding a splash of green to a corner, desk or cabinet.