Most terrariums should be placed in bright indirect light. That’s because most plants need a lot of light to survive since sunlight is used by plants (via photosynthesis) to make food.
In general, succulents and cacti are adapted for life in direct sun, while mosses and tropical plants require more protection from intense sun rays.
Too much or too little light can stress or kill a plant, however, so it’s important to consider which plants you’re growing before you decide how much light you need.
Let’s talk about requirements for each type of plant you might be growing.
Terrarium Light Needs Depend on Which Plants You Grow
The key to a healthy plant is to keep it in its ideal environment. When it comes to light, the type and amount of light that you need depends on what types of plants you have.
A lot of the time, tropical terrarium plants are low-light, meaning they may be able to get by with less direct sunlight; because, most tropical plants originate from the shaded forest floor and are not used to intense sunlight.
An example of these plants would be:
- Arrowhead Plants
- Rippled Peperomia
Carnivorous terrariums like Venus flytraps need bright indirect light — they will do best near a north or east facing window where they can get a decent amount of sunlight each day.
Succulent and air plant terrariums also need bright indirect light, with the exception of some low light succulents like snake plants.
Choosing Terrarium Plants Based on Light Needs
The amount of light your terrarium gets depends on its location, so make sure you choose plants that will thrive in the same amount of light.
For example, if you have a terrarium that is in low light, then you can grow plants like ferns, mosses and Peperomia.
If your terrarium is in moderate to bright light then you can grow plants like succulents and cacti.
When choosing plants for your terrarium it’s important to consider their mature size as well as their light requirements.
Make sure your chosen plants will all fit inside the container when they are fully grown, and keep in mind how fast they grow relative to one another.
For a healthy display you want to avoid overcrowding or shading out smaller or slower growing plants with larger ones.
In some cases, this may mean planting lower light plants beneath taller ones, or simply leaving out a plant that requires more space than there is room for it to grow.
You may also want to leave areas along the edges of containers unplanted to increase light penetration if there are no other parts of the container where this occurs naturally.
Carnivorous Plants Need a Lot of Light
Carnivorous plants are a popular choice for terrariums. If you have a carnivorous plant terrarium, or if you’re thinking about making one, there are some important things to know about lighting.
Most carnivorous plants need bright indirect light or artificial grow lights. You should place them in south or north facing windows so they can get light, but not in direct sunlight.
Carnivorous plants need more light than most air plants, moss, and many tropical terrarium plants.
Depending on the type of carnivorous plant you have, the amount of sun it needs can vary significantly, however. Pitcher plants, for example, need 25,000 lux (PAR is what you’d normally use to measure light for plants, but Lux is easier to measure) for at least 12 hours per day.
Heart-leaf sundew plants, on the other hand, can be grown under a lamp without any special lighting at all.
Most carnivorous plants do require a lot of bright light for at least 8 to 12 hours per day, however.
If your carnivorous plant is growing well and producing new leaves, that’s usually the best indication that it has enough sun. If your carnivorous plant starts to lose its color or start looking shriveled, you might want to move it to a brighter spot.
If you want to know more about how much light your specific carnivorous plant needs, check out this article from the International Carnivorous Plant Society.
Succulent Terrariums Depend on Which Ones You Grow
For most common types of succulents, you should place your terrarium in a spot that receives bright, indirect sunlight. An area next to a north or south facing window is usually the best option, as it will receive the most light throughout the day.
If you don’t receive enough natural light to meet your succulent’s needs, you can use artificial grow lights to supplement the light it receives from the window or make up for lack of natural light altogether.
Most succulents need at least 4 to 6 hours of bright, indirect sunlight each day.
If you’re using artificial lights, it’s important that you make sure that your artificial light has the correct color temperature so it can properly support photosynthesis. Light towards the cooler end of the spectrum (e.g. 4,000K or higher – also called daylight bulbs) are better than warm or soft white bulbs.
High light succulents include:
- Hens and Chicks
- Most Cacti
Also, keep in mind that some types of succulents do not require as much sun as others and are better suited to low-light environments making them good options for those who struggle with providing adequate lighting for their terrariums.
Examples of low light succulents would be:
- Snake Plants
- Ox Tongue
- Aloe Aristata
- Mistletoe Cactus
- String Of Hearts
Moss terrariums can be placed in areas with low light.
When it comes to picking a location for your moss terrarium, you have a lot of options. Mosses are one of the few plants that can survive on low levels of light. In fact, many mosses grow wild in forests where sunlight rarely reaches them!
If you’re picking a location for your terrarium, choosing an area with some sort of indirect light is better than nothing at all—even just near a lamp should do. Remember, most mosses are found living in shady conditions on the forest floor or on rocks and trees, so they tend to be sensitive to light.
As long as there is no direct sunlight shining into the container throughout the day, you should be fine placing your terrarium anywhere in your home or office. Some good examples would be on a desk near your desk light, in bookcases, or inside of glass shelving units such as china cabinets.
Air plants need either bright indirect sunlight from a south facing window or artificial light
Air plants need bright, indirect light. If you have a south facing window, that’s great. You can place your terrarium somewhere near that window and forgo artificial lighting.
But if you don’t have a south facing window, or if the window is too far from where you have your terrarium, then artificial light will be needed to supplement the natural light.
Air plants need about 6-12 hours of bright indirect light per day to survive and thrive.
Takeaways: With the right amount of light, you can keep your terrarium happy for years to come!
The key to a healthy terrarium is keeping your plants in their ideal environment, so that they can grow and flourish. The type and amount of light that you need depends on what type of plants you have.
Carnivorous plant terrariums need bright indirect light—at least 4-6 hours of direct sunlight will help them thrive, but they’ll also be happy in the sunniest windowsill in the house.
Succulent terrariums also need lots of light since succulents are native to arid environments and tend to do better with bright light. Your succulents will be happiest by a south-facing window, where they will get more light throughout the day. Remember to keep an eye on your succulent for any signs of moisture or light stress if you live in a high-heat area!
Moss terrariums don’t need as much light as carnivorous or succulent ones—in fact, moss grows naturally under tree canopies where there isn’t much direct sunlight—but once again it depends on the type of moss species you’re using. Some like bright indirect light while others prefer low-light or shade conditions.