---
title: "Best Indoor Plants for Oxygen: Which Ones Give Oxygen 24 Hours?"
description: "Snake plant, aloe, tulsi and orchids release oxygen at night — here is why, how much it actually amounts to, and the 10 highest oxygen producing indoor plants."
url: https://upflat.online/blog/best-indoor-plants-for-oxygen
category: air-wellbeing
tags: ["oxygen", "plant picks", "research", "bedroom"]
published: 2026-02-05
updated: 2026-08-22
author: "Mara Ellis, Horticulturist & founder"
reading_time_minutes: 5
license: "Quotation permitted with attribution and a link to the source URL."
---

# Best Indoor Plants for Oxygen: Which Ones Give Oxygen 24 Hours?

**Short answer:**

- CAM plants — snake plant, aloe, tulsi, orchids — open their pores at night and release oxygen then.
- Total output depends on leaf area and light, so a big areca palm beats any small 'oxygen plant'.
- No practical number of houseplants changes a room's oxygen level; ventilation does that.

## Key takeaways

- Oxygen output scales with leaf area and light — a big plant in a bright room produces most.
- CAM plants (snake plant, aloe, tulsi, orchids) release oxygen at night rather than during the day.
- A room's oxygen concentration is not measurably changed by houseplants; ventilation dominates completely.
- The night-oxygen plants are still excellent bedroom plants for other reasons.

Two questions sit behind every search for oxygen plants: which plant produces the most, and which produces it at night. Both have real botanical answers, and they are genuinely interesting. Both also come with a piece of arithmetic that almost never gets mentioned alongside them, so it is included here — not to spoil the idea, but because you deserve to know what a plant can and cannot do before you buy one for that reason.

## Why some plants give oxygen at night

Most plants use C3 photosynthesis: they open their stomata during the day, take in CO₂, and release oxygen while the light lasts. At night the process stops and they respire like any other organism.

Plants from hot, dry environments evolved a workaround called crassulacean acid metabolism, or CAM. To avoid losing water in daytime heat, they keep their stomata shut during the day and open them at night, storing CO₂ as an acid until morning. A side effect of that gas exchange is that CAM plants release some oxygen after dark — which is the entire basis of the '24 hours oxygen' claim.

*CAM plants — the ones that exchange gases at night.*
| Plant | Botanical name | Light | Difficulty |
| --- | --- | --- | --- |
| Snake plant | Dracaena trifasciata | Low to full sun | Very easy |
| Aloe vera | Aloe barbadensis | Bright to direct | Easy |
| Tulsi / holy basil | Ocimum tenuiflorum | Direct sun, 4–6 hrs | Moderate |
| Orchid | Phalaenopsis | Bright indirect | Moderate |
| Christmas cactus | Schlumbergera | Bright indirect | Easy |
| Jade plant | Crassula ovata | Bright to direct | Very easy |
| Bromeliad | Guzmania, Neoregelia | Bright indirect | Easy |
| Peperomia | Peperomia obtusifolia | Moderate to bright | Very easy |

## Which plants produce the most oxygen overall

Total oxygen output is a function of two things: how much leaf area a plant has, and how much light reaches it. Species matters far less than size. A two-metre areca palm in a bright room out-produces a shelf of small succulents many times over, whatever the species lists say.

1. **Areca palm** — large frond area, fast growth, the highest practical output of any common indoor plant.
2. **Rubber plant** — big, thick leaves and vigorous growth in bright light.
3. **Money plant / pothos** — modest per leaf, but a mature vine carries an enormous number of leaves.
4. **Peace lily** — good leaf area and productive even in moderate light.
5. **Spider plant** — dense clumps of leaves plus plantlets, all photosynthesising.
6. **Weeping fig** (*Ficus benjamina*) — thousands of small leaves add up to a large total area.
7. **Bamboo palm** — tall, leafy and tolerant of indoor conditions.
8. **Boston fern** — very high surface area, though only in humid conditions.
9. **Snake plant** — moderate output, but uniquely delivered at night.
10. **Tulsi** — modest in size, but the most productive of the small CAM plants in real sun.

## The arithmetic nobody includes

Air is about 21% oxygen. A typical bedroom holds roughly 30,000 litres of air, containing around 6,000 litres of oxygen. A healthy houseplant in good light might produce somewhere in the region of five to ten litres of oxygen a day — and consumes a portion of that itself through respiration. Against a background of 6,000 litres, constantly exchanged with outdoor air through gaps, doors and ventilation, the contribution is immeasurably small.

> **What this means in practice**
> You cannot raise the oxygen level of a room with plants, and you do not need to — normal ventilation does it continuously. Choose oxygen plants because they are attractive and tough, and because CAM species happen to be among the most drought-tolerant houseplants there are.

## Tulsi indoors

Tulsi deserves a separate note because it is so often recommended for indoor oxygen and so often dies indoors. It is a sun plant: it needs four to six hours of direct sunlight, which in practice means a south-facing windowsill or a balcony, not a shelf in a living room. Given less, it stretches, thins and goes woody within a couple of months. Keep it in the brightest position you have, water when the top 2 cm dries, and pinch the growing tips regularly to keep it bushy.

**Figure: Night oxygen vs total oxygen**

Two different questions, two different answers. Neither changes the oxygen level of a room, but both are worth understanding before you buy on the strength of a claim.

## Getting the most from what you have

1. **Prioritise light over species** — The same plant in a bright spot photosynthesises several times faster than in a dim one. Moving a plant a metre closer to the window does more than swapping it for a 'better' species.
2. **Choose bigger plants** — Leaf area is the variable that matters. One large palm beats a dozen small pots.
3. **Keep leaves clean** — Dust reduces the light reaching the leaf surface by a fifth or more. Wipe large leaves monthly with a damp cloth.
4. **Do not crowd** — Plants shading each other reduces total photosynthesis. Space them so each gets light.
5. **Open a window** — The single most effective thing you can do for the air you breathe indoors, and it costs nothing. Our [air purifying plants guide](/blog/air-purifying-indoor-plants) works through why.

## Frequently asked questions

### Which indoor plant gives oxygen 24 hours?

CAM plants — snake plant, aloe vera, tulsi, orchids, bromeliads, jade plant and Christmas cactus — open their stomata at night and release oxygen after dark as well as, in some cases, during the day. The quantities are very small.

### Which indoor plant gives the most oxygen?

The areca palm, because oxygen output depends mainly on leaf area and growth rate rather than species. Any large, fast-growing plant in bright light will out-produce a small one, whatever its reputation.

### How many plants do you need to oxygenate a room?

More than would fit. A room's oxygen supply is dominated by air exchange with outdoors, and a houseplant contributes a few litres a day against a background of thousands. No practical number of plants changes a room's oxygen level.

### Is it good to keep a snake plant in the bedroom?

Yes, though not for the oxygen. It tolerates the low light and cool temperatures of a bedroom, survives weeks without water, and needs no humidity. The night-time oxygen it releases is real but far too small to affect you.

### Can tulsi be grown indoors?

Only in a very bright position — four to six hours of direct sun, which usually means a south-facing windowsill or balcony. In ordinary indoor light tulsi stretches, thins and turns woody within a few months.

## Sources

- Interior landscape plants for indoor air pollution abatement — NASA Technical Reports Server, 1989. https://ntrs.nasa.gov/citations/19930073077
- Potted plants do not improve indoor air quality: a review and analysis of reported VOC removal efficiencies — Journal of Exposure Science & Environmental Epidemiology, 2020. https://www.nature.com/articles/s41370-019-0175-9
- Indoor Air Quality (IAQ) — US Environmental Protection Agency. https://www.epa.gov/indoor-air-quality-iaq
- Plant Finder — Missouri Botanical Garden. https://www.missouribotanicalgarden.org/plantfinder/plantfindersearch.aspx

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Source: https://upflat.online/blog/best-indoor-plants-for-oxygen — Upflat, written by Mara Ellis, reviewed 2026-08-22.