HouseplantsCorner is reader-supported. We may earn commissions if you buy through our links.

Can Plants Kill You At Night? (Solved & Explained!)

When I was a child, my grandma wouldn’t keep plants in the bedroom because at night, plants would breathe in the oxygen from the room.

I also have heard about plants being removed from hospital rooms because of this same belief.

You might be familiar with this story, but is it true? Will plants breathe in your oxygen at night and can they put you in danger?

In this article, you will learn if it’s safe to keep plants in the bedroom at night and how many you can keep.

Here’s Whether Plants Can Really Kill You At Night:

There is absolutely no chance your houseplants can breathe your oxygen and kill you. While most plants take oxygen in and release carbon dioxide at night, overall, plants release more oxygen than they take in. That means plants will increase oxygen levels overall.

Also, the amount of oxygen plants breathe in is much less than what a human or a pet does, so you have nothing to worry about.

The reason why this myth still persists is because of the misunderstanding of photosynthesis.

We were shown diagrams since we were children of photosynthesis being equal to respiration in plants, so people tend to think of it as always a reverse phenomenon which is not true.

While it is true that a single leaf plant will produce the same amount of oxygen as carbon dioxide, plant respiration happens at a slower pace than photosynthesis, which means that for every cycle you have a tiny gain of oxygen.

Otherwise, the plant wouldn’t grow.

Can plants kill you at night? photosynthesis vs cellular respiration diagram

You have probably seen the diagram above many times, but they usually don’t show the speed difference between respiration and photosynthesis.

So now that we got that out of the way, what if we are talking about a lot of plants confined into a small space? Let’s dig into that a bit.

Can Too Many Plants Kill You?

Let’s make this thought experiment because at the end of the day, plants technically still take oxygen during the night.

What if I live in a really small room and I fill it up with plants just for the night?

So, theoretically, they haven’t given any oxygen during the day but they will take oxygen during the night.

In this scenario, let’s assume we use as many plants as possible, can too many plants kill you?

The answer is no. It doesn’t really matter how many plants you have in a small room. It isn’t possible to put that many plants into the room that they eventually harm or kill you through oxygen deprivation.

It is actually more deadly not to have plants in your bedroom. Let me explain this with some numbers.

The part of the plant that does photosynthesis and respiration is the leaf. Let’s completely ignore the fact that they give off more oxygen than they consume for now.

The medium ratio between oxygen consumed per kilogram is 100:1 between plants and mammals. Meaning at the same weight, mammals consume 100 times more oxygen than plants.

I personally sleep in the same room with my dog and my husband. If we add up their weights, we would have around 220 pounds so 100kg of hairy cuteness.

If we calculate how many plants we would need using the ratio above, we would need 22.000 pounds (10.000kg) of plants in the same room just so the breath in the same amount of oxygen as my husband and my dog does.

We can make a nice round number and say we would need 1000 plants weighing in at 22 pounds each (10kg) counting the soil, stem, and roots, just to consume as much as a big adult in the room. Wow, those are a lot of plants even for me.

So I hope that settles it and gives you some peace of mind.

But wait, there is another problem with this. Too much oxygen can also harm or kill you.

We already established that plants give off more oxygen than they use, so, could plants theoretically produce so much oxygen that they can give you oxygen poisoning?

In this case I won’t even go in detail with the calculation because the positive output of oxygen it’s small when it comes to your average plant in 24-hours.

You will also need to achieve a 100% oxygen level.

You would need about 660 million average plants in a small room in order to kill someone with oxygen poisoning.

Not only is that impossible because of the sheer number of plants, but they would need carbon dioxide and light to make it work, which means the plants will end up dying before killing the person.

So, there you go, no real amount of plants can kill you by taking or giving too much oxygen.

I know this is a weird way to think about it but if all the plants were to breathe in more oxygen than they release, we would all be dead right now.

But maybe there are certain situations where you should avoid having plants in your bedroom, let’s explore that further.

Is It Bad To Sleep With Plants In Your Bedroom?

Can plants kill you at night? Houseplant in bedroom

It is not bad for you to sleep with plants in your bedroom, especially if you are a healthy adult and your houseplants are healthy.

Not only is it not bad but it’s actually really good for you.

I can personally attest that plants can actually help a lot with sleeping and breathing better.

There also have been multiple studies done that suggest plants can actually help a lot while sleeping.

Plants will increase oxygen levels in your room while reducing carbon monoxide and carbon dioxide, which helps a lot with sleep apnea and asthma.

Plants also reduce quantities of natural toxins like methane and formaldehyde. They can act as filters reducing harmful pollutants that are inescapable in modern life and will help you with better breathing.

Houseplants can also add a pleasant scent and color to your room, which helps with depression, anxiety, and improves cognitive functions and sleep quality.

The benefits that houseplants can have on your life are hard to overstate and having asthma myself, I can sincerely say that I sleep and feel much healthier having plants in my room.

This being said, there are certain special conditions where you might not want to have plants in your bedroom, like these ones:

  • If you have hay fever, avoid plants with an overpowering scent.

  • If the plant is not healthy and suffering from fungus or has mold in the soil. You need to be extra careful with this if you have asthma or allergic reactions.

  • A couple of plants that you might want to avoid having in your room if you have small children or pets because they are toxic if ingested and have a history of being appealing to eat.

Although this can be a long list, I will state those that are common houseplants and which look appealing to pets:

1. Daffodil (Narcissus)

Toxic bulbs that can cause dermatitis if you touch them and are toxic if consumed. They cause stomach upsets and vomiting with the most severe reactions on this list.

2. Caladium (Elephant ear)

 They are toxic if consumed causing burning in the throat and mouth. Their leaves can look pretty spectacular, inviting pets or children to stick them in their mouths.

3. Devil’s Ivy (Pothos)

They look harmless and are safe to the touch, but toxic if consumed. Pothos cause pain, swelling and vomiting to both pets and humans.

4. Dumb Cane

Toxic if consumed and apparently it happens often enough to give the plant its name. The effects are swelling of the tongue and mouth with difficulty speaking.

5. Peace Lily​

Safe to touch, but toxic if consumed. They are pretty and smell good, so if you have pets or small children avoid them as they might want to munch on them.​

There are tons of alternatives to these plants, and if you don’t have any pets or small children or the impulse of eating them, you are still safe to have them in the bedroom.

Especially Peace Lilies, who have a great scent at night and how the now-famous NASA experiment showed, are great at cleaning the air.

If you have an interest and want to read more here is the experiment quick overview.

Do Plants Take In Oxygen At Night?

Yes, during the night, plants enter a process called respiration, where they use oxygen by combining it with the food they create during photosynthesis.

But the truth is, plants respire all the time, night and day.

The result of the process is carbon dioxide, so you can say respiration is the opposite of photosynthesis.

Wait, what? But I thought plants only take oxygen at night, how can we test this?

If you have the time, I suggest you try out the following very simple experiment:

Plant respiration experiment

Materials you will need:

  1. Your favorite houseplant, if it’s too big, take a smaller one.

  2. A shallow bowl of water. It’s easier to spot if it is transparent or has a darker color.

  3. Sunlight. Make sure you have sunlight available, so we can actually test respiration during the day.

Now follow the steps below:

Step 1

Submerge one leaf of the plant underwater. It will try to float but try to keep at least one leaf completely submerged.

Step 2

Put the bowl and the plant in the window or in a place it gets sunlight.

Step 3

Leave it for one hour.

Step 4

Look at the leaf surface underwater. You will see a few small bubbles as the plant respires.

There you go, plants use oxygen all the time, so the myth that plants can kill you at night really stands on nothing at this point.

To make things even better, there are houseplants that give oxygen 24 hours a day, so if you really want to make sure you get the best benefits, keep the next houseplants in mind.

Houseplants That Give Oxygen At Night

Yes, you’ve read this right, there are popular houseplants that will give oxygen even during the night.


Can plants kill you at night? Gerbera flowers in the dark

Gerberas are absolutely perfect if you are picky. They are non-toxic and easy enough to take care of.

They are also scentless so If you suffer from hay fever, there is nothing to worry about.

Besides the non-stop oxygen, they also flower and give a beautiful spark of color to your room that can help with anxiety and depression.

Aloe Vera

Can plants kill you at night? Aloe vera plant

Aloe Vera needs no introduction. In my personal opinion, it is one of the best houseplants anyone could own.

Besides the amazing properties Aloe Vera has, it also gives oxygen during the night.

The latex it contains is toxic if you or your pet ingest but in my experience that’s a highly unlikely thing to occur.

Snake plant

Can plants kill you at night? Snake plant

Similarly to Aloe Vera, Snake Plants can be mildly toxic if ingested, but the truth is it doesn’t happen too often.

They are also great rugged plants that can outstand almost anything and can clean the air like very few plants could.

Areca palm

Can plants kill you at night? Areca palm

Areca palms are more popular than ever and it might be the time you get one too.

The reason why I recommend them is that they can get pretty big and can single-handedly satisfy the need for a plant in the bedroom.

You can only have one areca palm in the corner of your bedroom and you’re good to go, it will clean the air even during the night and also give oxygen.

There are tens or hundreds more plants that give oxygen at night, including the Peace Lily mentioned above.

If you are in the mood of reading a bit of science today, you can check out this official NASA paper on the benefits of houseplants

I really hope this puts an end to this internet myth and we all get to enjoy a bit more plants in our lives.

Related Posts