orchid related, but also general plant ?
 

so there's this ongoing argument in the house that has persisted since the girl and i have been together. i want an answer!! :D

plants in the bedroom.

she is from spain, and i am an american. she insists that the old knowledge from her neck of the woods is that it is bad to have plants growing in the bedroom...something about the air quality at night.

i have never heard this and believe its folklore. now, i want to permanently house a few orchids in some prime orchid realestate that has been thus far spared from development.

i've had plants in my bedroom for years....so maybe there is some credibility to what she says as obvs i hae a few screws loose :waving is there any merit to this belief?

thanks for any input!!

I first heard of this argument in the early 1960s. It could only have originated with somebody who barely understood how plants function.

If your girlfriend is worried about running out of oxygen, remind her you use hundreds of times more oxygen than any plants in your room. It would make more sense from her perspective to keep the plants in the room and get rid of you.

Most plants take in carbon dioxide and release oxygen during the day. They take in oxygen at night, but not very much. I mean a tiny amount. People use very large amounts of oxygen day and night.

C4 plants, like many orchids, take in carbon dioxide at night. They release oxygen during the day but don't take it in at night.

Unless your room is so tightly sealed there is no gas exchange there will be plenty of oxygen flowing in to replace the amounts you and the plants use. If your room were that tightly sealed, just one person would quickly use all the oxygen and die of hypoxia. But rooms aren't that tightly sealed. Plants don't take in nearly as much oxygen as a person does.

I hope someone with more book learnin’ will correct me, but my understanding is that plants’ uptake and release of oxygen and carbon dioxide gases is more-or-less passive; the stomata open, and the concentrations of dissolved gases inside the plant and outside the plant start to equilibrate.

don't tell her this....

but you have heard this also before then?? hmmmm....

and ray, i've tried the biological approach, but it ain't working!

What an odd bit of folklore! I wonder where that started?

Plants vs no plants is an argument that's been ongoing for decades. It's definitely not an American vs Spanish debate.

Having said that, are you sure the gal isn't just practicing the philosophy of feng shui? :biggrin:

Do you happen to let pets sleep in your room? Folks use to believe that a cat in a baby's crib would deplete the oxygen as well or harm the child. Both would be a welcome addition for me.

Yes, the gases flow passively through the pores only when open, down a concentration gradient. In the daytime CO2 is used inside C3 plants and converted to sugar, so the concentration of CO2 is higher outside the plant. It flows into the plant. O2 is produced and it flows out of the plant. At night C3 plants aren't fixing CO2 and the pores are closed, so there is no CO2 flow. Plants need a little bit of energy to stay alive at night, so they oxidize sugars with oxygen remaining in the plant, plus whatever tiny amount leaks through closed pores.

C4 plants, including many orchids, open pores at night and take in CO2. They don't perform photosynthesis at night so they don't release O2 then. They take in a little O2 for metabolism, more than C3 plants because fixing CO2 requires energy. But it's not much.

Cacti, C4 plants, are done fixing CO2 by midnight because the pH steadily falls as CO2 is fixed, and the necessary enzymes stop working when the pH gets too low.

But the upshot is plants aren't dangerous in bedrooms.

If the plants need to stay in one small area of the house, what about clothing, jewelry and beauty products?

That line of thinking is a lot like the myth of fan death commonly believed in South Korea.

I could see the no-plants-in-the-bedroom myth originating from the phenomena of overnight fish kills in heavily planted ponds and waterways. At night the fish and plants use dissolved oxygen for respiration and if there are too many plants and/or if the water is really warm (warm water holds much less dissolved O2 at saturation than cold water) the O2 levels can drop to lethal levels resulting in dead fish the following morning. Non-scientists latch onto the "too many plants used up the O2" part and it's only a short leap from there.

Btw, tell your SO that there are plants growing on the ISS and astronauts survive just fine. :D

People believe a lot of dumb stuff and have an amazing ability to believe exactly what they want to believe without any evidence or logic. The greatest lesson I've learned from the past couple of years.