No, typical houseplants do not significantly purify indoor air in real homes or offices. The famous 1989 NASA study showed plants can remove some pollutants in sealed chambers, but recent research proves you’d need hundreds or thousands of plants to make a noticeable difference in normal rooms—far more than most people have. Houseplants offer many other wonderful benefits for beginners!
Hey there, friend! If you’re like many new plant lovers, you’ve probably heard that houseplants are amazing at cleaning the air in your home. It’s a popular idea that pops up everywhere—from blogs to home decor tips. But does it really work that way? Many people feel excited about their green friends helping with air quality, only to wonder if it’s true or just a nice story.
The truth is, this belief comes mostly from an old NASA study, but science has looked closer since then. Don’t worry—I’m here to walk you through it step by step in a simple way. We’ll look at the facts, what really happens with houseplants and air, and why adding plants to your space is still one of the best things you can do. By the end, you’ll feel clear and confident about your indoor garden. Let’s dig in!
What the Famous NASA Study Actually Said
Back in 1989, NASA did research on how plants might help clean air in space stations—places with no fresh air from outside. They tested common houseplants in small, sealed chambers. The results? Plants like peace lilies, spider plants, and snake plants removed some harmful chemicals called volatile organic compounds (VOCs), such as formaldehyde and benzene. The study suggested plants and their soil microbes could absorb these pollutants.
You can read the original NASA report here on the NASA Technical Reports Server. It was exciting news at the time! Many articles and lists still share “NASA-approved air-purifying plants” based on this.
Why It Doesn’t Work the Same in Your Home
Here’s the key part: NASA’s tests happened in tiny, completely sealed boxes with no air flow. Real homes and offices are different. They have windows, doors, vents, and fresh air coming in (even a little). This natural air exchange dilutes pollutants much faster than plants can remove them.
A big review by researchers at Drexel University looked at dozens of studies over 30 years. They found that plants remove VOCs very slowly compared to how quickly air moves in a normal room. To match the cleaning power seen in lab tests, you’d need 10 to 1,000 plants per square meter of floor space—that’s hundreds or even thousands in a typical living room!
The American Lung Association explains this well: the NASA study worked in closed chambers, but not in everyday spaces. Check their clear summary here.
Real Benefits of Houseplants (Beyond Air Cleaning)
Even if they don’t act like super air filters, houseplants bring tons of joy and real value to your home. Here’s why they’re worth every bit of care:
- They boost your mood and reduce stress—studies show just looking at plants or tending them lowers anxiety.
- They increase humidity a little through transpiration, which feels nice in dry rooms.
- They make spaces prettier and more alive—green leaves brighten any corner!
- Caring for them builds a relaxing routine and connects you to nature indoors.
- They teach patience and reward you with new growth.
Many beginners start with plants for “air purification” but stay for the happiness they bring. That’s the real magic.
Common Houseplants People Thought Were Air Purifiers
Here are some popular ones from the NASA list—and why they’re still great choices for beginners:
| Plant Name | Common Name | Easy to Care For? | Best For | Light Needs |
|---|---|---|---|---|
| Spathiphyllum | Peace Lily | Yes | Low light, pretty flowers | Low to medium |
| Chlorophytum comosum | Spider Plant | Very easy | Beginners, hanging baskets | Medium |
| Sansevieria trifasciata | Snake Plant | Super tough | Neglect-proof, bedrooms | Low |
| Epipremnum aureum | Pothos | Very easy | Trailing, offices | Low to bright |
| Chamaedorea seifrizii | Bamboo Palm | Moderate | Tropical look | Medium |
These are all forgiving and beautiful—perfect for new gardeners like you.
How Many Plants Would You Really Need?
Let’s make it clear with numbers from the research. In a normal 1,500 square foot home, studies suggest you’d need:
- At least 680 plants to see any real VOC removal (that’s like filling every surface!)
- Or 10–100 plants per square meter for lab-like results (impractical for most homes)
| Room Size (sq ft) | Plants Needed for Noticeable Effect (per research estimates) | Realistic for Beginners? |
|---|---|---|
| 100–200 (small bedroom) | 100–500+ | No—too many! |
| 300–500 (living room) | 300–1,000+ | No |
| Whole home (1,500 sq ft) | 600–10,000+ | Definitely not |
See? It’s not about a few pots on the windowsill. Focus on enjoying a handful of healthy plants instead.
Better Ways to Improve Indoor Air Quality
If clean air matters to you, try these practical steps:
- Open windows when weather allows—fresh air exchange is the best natural cleaner.
- Use an air purifier with a HEPA filter for dust and allergens.
- Avoid smoking indoors and use low-VOC paints/products.
- Keep humidity in check (30–50%) to prevent mold.
- Change HVAC filters regularly.
Plants fit beautifully into a healthy home—they just aren’t the main air fixers.
FAQ
Do houseplants increase oxygen levels indoors?
A tiny bit during the day through photosynthesis, but not enough to notice. Your home’s air exchange handles oxygen just fine.
Which houseplant removes the most toxins according to NASA?
In their sealed tests, plants like peace lily and spider plant did well with certain chemicals—but remember, it doesn’t scale to real rooms.
Can too many houseplants make air worse?
Very rarely. Overwatering can cause mold, but normal care keeps things healthy.
Do plants help with allergies?
They might add a bit of humidity and reduce stress, but they don’t filter allergens like dust or pollen effectively. Some people are even allergic to plant pollen.
Are there any plants that truly clean air better?
No common houseplant does it meaningfully in normal homes. Engineered systems with many plants and fans might work, but that’s not typical potted plants.
Should I stop buying houseplants if they don’t purify air?
No way! They’re fantastic for mental health, beauty, and fun. Keep growing them for the joy they bring.
What if I have a very sealed, energy-efficient home?
Plants might help a tiny bit more there, but ventilation or purifiers are still better first steps.
Wrapping It Up: Enjoy Your Plants with Realistic Expectations
There you have it—houseplants aren’t miracle air purifiers in everyday homes, despite what the old NASA headlines suggested. Modern science shows the effect is too small to count on for real cleaning. But that doesn’t make them any less wonderful!
As your gardening friend, I encourage you to fill your space with green life anyway. Start small with easy ones like snake plants or pothos. Watch them grow, learn their needs, and feel that happy boost every time you see them thriving. Gardening is about joy, learning, and connecting to nature—not perfection.
Keep it simple, water when needed, give them good light, and enjoy the process. You’ve got this! Your home will feel warmer, calmer, and more alive with plants around. Drop any questions below—I’m always here to help you grow confident and happy with your green friends.
Happy planting!