[johnsimer]

IIRC you need ~300 plants to offset every one human in a house

[jefftk]

Yes, it's impractically high: we exhale about 1kg of carbon daily, so your plants collectively need to be getting about 1kg heavier daily to absorb that.

[alexey-salmin]

It's an order of magnitude worse than that, plants are mostly water, not carbon. They'll gain tens of kilos per day.

If you can feed off your house plants alone, then you have a chance of closing the carbon loop. This was tried (e.g. biosphere2) and it's extremely hard even at the industrial scale.

[CGamesPlay]

Don’t the plants exhale oxygen? So they won’t be getting 1kg heavier, closer to 300g, but I don’t know the actual chemistry.

[mrob]

About 1kg of carbon dioxide, not carbon. 1kg of CO2 is only about 0.27kg carbon.

[SoftTalker]

Yeah it was sort of a joke, but having houseplants will make some difference. Not that they would be practical to absorb all the CO2 in the air. On the downside, keeping indoor plants healthy does take some ongoing time and effort and isn't everyone's cup of tea.

[mistrial9]

this ignores "system balance" and assumes "closed system" no? In other words, no one says that plants alone will compensate.. but instead they tip a system in a more favorable direction.. Plus some people really respond to house plants in lots of complimentary positive ways.

[Jarmsy]

More like 700 according to this

https://medium.com/@candidegardening/how-many-plants-would-i...