How much CO2 can plants live in? If plants were raised in a greenhouse how much CO2 would be too much?

Question

Assuming all the light, water and food was provided and only the CO2 level was raised how high would the CO2 level have to get to harm the plants?

Answer 1

A lot. It would have to get to the point acidifying their tissue. (carbonic acid -- it is what CO2 becomes in water)

Plants need some oxygen too. I'm sure that a 100% CO2 atmosphere would eventually kill them from lack of O2 and possibly from lack of H2O.

It looks like plants can live for a while in a 100% CO2 atmosphere, at least 48 hours. So maybe if you put them in more than one atmosphere of CO2. You could do this experiment by putting an aquarium plant in a bottle of club soda and s******g the cap back on.