So you’ve probably heard that carnivorous plants should be raised in a terrarium. But that raises the question, do you really need a terrarium to do it?
The short answer is no, but it can be beneficial for tropical species. The reason why it’s recommended to grow them in a terrarium is because of the higher humidity a terrarium provides. But if you can maintain the right humidity levels without a terrarium, you shouldn’t need a terrarium to grow your carnivorous plants.
Now that you know the short answer, let’s get into the actual reasons behind why a terrarium isn’t always appropriate for carnivorous plants.
Can you put carnivorous plants in a terrarium?
A common assumption that everyone has about carnivorous plants is that they all need high humidity. So the natural follow-on conclusion is that they should go in a terrarium because terrariums are good for plants that enjoy high humidity.
This assumption is not always true.
While many species do prefer high humidity environments, that does not necessarily mean that all of them do. The key factor to consider here is your plants’ natural habitat. It’s always best to do your research first to determine if your plant prefers a tropical environment or a more temperate one.
Temperate plants such as the venus flytrap and sarracenia are not recommended for a closed terrarium. They tend to prefer lower temperatures and will require an annual dormancy period to stay healthy. This means that they will need a season of lower sunlight and lower temperatures than normal. In their growth season, it may be difficult to maintain lower temperatures inside of a terrarium, especially if your plants also need full sun.
If your plants require full sun, there’s also going to be the additional challenge of making sure they get enough sunlight without cranking up the heat inside the terrarium. In a closed container, it’s basically functioning like a mini greenhouse. This is definitely going to be a problem if you’re trying to grow temperate plants in your terrarium that prefer the lower end of the temperature range.
Tropical plants on the other hand might stand a chance at growing inside of a terrarium. They are more tolerant of higher humidity and higher temperatures. The only thing to note is that tropical plants tend to be on a larger side in terms of size and will require some pruning to prevent them from touching the walls of the container.
The nice thing about sticking with tropical plants is that they don’t need a dormancy period. This means you won’t have to worry about changing the temperature in your terrarium every winter season.
There’s also the question of air circulation. If you are choosing to put your plants in a closed terrarium, there’s going to be no air circulation and some mineral buildup. Stagnant air could lead to problems with mold growth and if there’s a lack of drainage, that could also promote root rot.
Since most carnivorous plants are used to getting their nutrients from their insect prey rather than from the soil, any extra minerals in nutrients found in the soil could do more harm than good.
There’s also the additional struggle of feeding your plants insects. If there’s no way for insects to reach your plants, your plants will have no way to feed unless you manually feed them insects yourself.
The other challenge with growing plants in a terrarium is that there might not be sufficient drainage for your plants needs. This is why it’s critical to include a drainage layer so that minerals can be flushed out for plants that prefer soil with poor nutrient content.
If you are going to grow your carnivorous plants in a terrarium, you should preferably do so with tropical plants. There are two types of tropical carnivorous plants: highland and lowland varieties.
Highland varieties come from higher elevations, which means they are more tolerant of cooler temperatures. Lowland varieties on the other hand require consistent temperatures year-round and will not do so well in colder temperatures.
If you have the option choose, you should stick to lowland variety tropical carnivorous plants. The natural habitat of these plants closely mimics the conditions of a closed terrarium: high temperatures and high humidity all year round.
Long story short, it might be difficult to replicate your carnivorous plants’ natural living conditions in an artificial terrarium. However, it can be done with the right choice of carnivorous plant.
What is a typical habitat for carnivorous plants?
When deciding how to grow your carnivorous plants, the most important factor to consider is if you can replicate your plants’ natural habitat.
The most common habitat for a carnivorous plant to grow in is a bog or a swamp. Bogs typically have plenty of water and light, low competition, and nutrient poor soil. Those that don’t live in bogs are generally tropical.
Carnivorous plants comprise a very diverse group of over 600 species of plants. About 3 new species are added every year. Despite this diversity, most carnivorous plants will tend to share some common characteristics.
Most carnivorous plants have adapted to grow in places where the soil is poor and nutrients, but where sunlight and water are abundantly available. Instead of getting their nutrition from the soil like most points do, they get most of their nutrients from trapping and consuming insects.
They tend to thrive in habitats that are atypical for most plants. If you think about it, growing structures that are designed to trap insects costs plants energy that could have been invested in reproduction.
The only way this will pay off from an evolutionary/natural selection perspective is if this is the only way they’re able to get nutrients. If there is plenty of nutrients from the soil, there is no competitive advantage for plants to invest in carnivory.
This is why most carnivorous plants will grow in places where there’s plenty of light and water, but limited soil nutrients. The more limiting the soil nutrients are, the more plants will invest in carnivory. Just like how cacti will only grow in areas with little water and will not do well if they’re given too much water.
What this means for you is that most carnivorous plants will not tolerate common tap or drinking water. This type of water contains minerals, such as calcium salts, that can quickly build up and kill carnivorous plants. Because of this, it’s often recommended to water them with distilled water or rain water.
Regardless of where they grow, most of them will require high humidity, given that they grow in areas with plenty of water readily available.
You might come across the terms “highland” and “lowland”. This refers to the elevation that the plant will grow at. Most likely you’ll see the term used to describe tropical pitcher plants. This distinction is important because it will give you a hint as to what temperature and conditions the plant will prefer as well as how it will grow.
Highland plants will prefer lower temperatures ranging from 55-70°F and will tend to grow smaller, while lowland plants will prefer higher temperatures around 70-90°F and will grow a little bit bigger then highland varieties.
Can carnivorous plants survive indoors?
Carnivorous plants can and are grown and cultivated indoors with the right conditions in place for them.
For most species, you’ll need to give them:
- Plenty of distilled or rain water
- Full sunlight
- High humidity
- Insects to feed on
- Nutrient poor soil
As long as these conditions are met, how you achieve them is not as important. But if you don’t achieve these conditions, they will have a noticeable impact on your plants’ health.
If your plants are being watered with tap water instead of distilled or rain water, the mineral build-up can lead to your plants’ demise.
If your plants are not getting plenty of sunlight, you might see them noticeably start to wilt. their leaves start to become droopy, and their traps start to lose their red coloration.
Carnivorous plants will also need nutrient poor soil like peat to mimic their nutrient poor soil found in their natural environments. Having an abundance of nutrients could actually burn your plants, causing damage to their roots.
Here are some ways you can grow carnivorous plants indoors:
- In a terrarium
- On the windowsill
- In a cooler
- In a greenhouse
There is one distinction that you will need to pay attention to regarding the species of carnivorous plant you’re growing. This distinction is whether or not your plant is temperate or tropical.
Some examples of tropical plants include:
- Asian pitcher plants
- Sun pitchers
- West australian pitcher plant
- Some types of sundews
Some examples of temperate plants include:
- Venus flytraps
- North American pitcher plants
- Cobra plants
- Some types of sundews
Temperate plants will do better in slightly lower temperatures and will require a dormant period during the winter season. You can artificially create a dormancy period by dropping the temperatures and lowering the sunlight it would normally get for a few months.
The venus flytrap, for example, prefers 86°F and goes dormant during cold winter months in their natural Carolinas environment, when temperatures drop under 32°F. It’s important to give them a cool season to give them a chance to go dormant.
This is a critical requirement for temperate carnivorous plants. If there is not a dormant season, plants will become weak and sickly after just a couple of years. The only exception is for young seedlings that often skipped their first dormancy period to get some extra growth in.
If you want to artificially create a “winter” environment, you would have to lower the temperatures and give it less sunlight. This could mean putting your plant in the shade for a bit rather than having them get full sun all day.
Tropical plants on the other hand do not require dormant season and will be fine with higher temperatures.
In terms of growing carnivorous plants in a terrarium, you will want to stick to tropical varieties of carnivorous plants. These plants will be more tolerant of high humidity and higher temperatures that might be more common in terrariums and greenhouses.
Which carnivorous plant is the easiest to grow?
If you’re just looking to grow a carnivorous plant with the best chances of finding success, here’s a list of a few that I’ve found online:
- Cape sunder drosera capensis
- Forked sundew drosera binata
- Yellow pitcher plant
- Early butterwort pinguicula primuliflora
- Terrestrial Bladderworts
Speaking a little bit more generally, tropical pitcher plants are probably your best bet for easy to grow plants. If you want to get more specific, pitcher plants of the highlander variety are going to be the easiest to grow.
Pitcher plants are all tropical plants, meaning they won’t need a dormancy period. Highlanders can generally be easily grown on your windowsill, with not too much additional effort.
If you want to grow your plants in a terrarium, you will want to lean towards tropical lowlanders since they will be more tolerant of higher humidities and higher temperatures.
Do carnivorous plants need to eat?
Carnivorous plants need to feed on insects to get their nutritional needs. In their natural habitats where they grow in nutrient poor soil, they rely on insects for valuable nutrients including nitrogen and potassium.
However, this does not mean that they need to feed everyday. So try your best to resist the temptation of having to do something active to keep your plant alive.
Most carnivorous plants will do fine on their own by feeding on any insects naturally flying around, especially if they are grown outdoors. After all, that’s what they do in their natural habitat. In fact, you could probably avoid feeding your plants insects at all. Feeding them too many insects could cause them to start wilting.
If you do decide to go ahead and feed them, stick to feeding your plants insects only and nothing that it wouldn’t catch naturally. You’re also going to want to feed them insects that aren’t any larger than about a third of the size of the trap. Feeding your plant insects that are too large could cause the trap to rot.
To mimic natural conditions of an insect being trapped by your plant, it may be helpful to stimulate the traps’ trigger hairs with a toothpick if you are feeding your plant dead bugs. This will mimic an insect struggling to escape from the trap, signaling to your plant that it’s caught something and that it should begin the digestion process.
If you’re growing them indoors where there are very few insects, you may be able to feed them insects on your own once every month or two, even down to once or twice a year. Carnivorous plants can go for pretty long periods without eating any insects at all.
Temperate carnivorous plants will also undergo a dormancy period where they will not eat any insects at all. This dormancy period helps them preserve their energy during winter months when there are fewer insects around to feed on in their natural habitats.
If you do choose to feed your carnivorous plants intentionally, fruit flies are always a good option. The easiest types to work with are wingless or flightless fruit flies. These guys will crawl right into the traps rather than fly away somewhere.
Some other options you can consider are:
- Freeze dried bloodworms
- Flake fish food
- Bean beetles
P.S. If at all possible, avoid teasing your plant and closing its traps artificially. Closing a trap costs your plant a lot of energy. Some plants will only trigger their traps a few times in their lifetime. Your plant definitely doesn’t want to waste those opportunities if it’s not going to catch anything.
Are carnivorous plants alive?
Yes, absolutely! And not just carnivorous plants, but all plants in general.
They are alive, but not in the way you might think.
You might not see them walk around, talk, or hunt for food, but they do meet the criteria for defining something as alive:
- They are responsive to the environment
- They grow and change
- They reproduce
- They have a metabolism
- They maintain homeostasis
- They are made of living cells
If you read through those characteristics, you’ll see that you yourself meet all those criteria as well as plants. Plants are alive just like animals.
Can a carnivorous plant eat a human?
Carnivorous plants do not eat humans. In fact, they couldn’t even if they tried. They simply do not have the mechanical structures or systems in place to trap and digest a human.
You may have heard stories of carnivorous plants eating people in stories like the little shop of horrors. But they are just stories that are not based on anything found in reality.
There have been no documented cases of carnivorous plants eating people.
So there’s no need to be afraid. Carnivorous plants can’t hurt you, even if they tried.
Thanks for reading. If you’re interested in learning more, check out the links below.