When I worked in a large commercial greenhouse they did it. I have never found the need to do it in my houses. maybe it is a difference between structure types and the ventilation they receive along with the amount of plants inside a house. We grew hundreds of thousands of mums, poinsettias, hanging baskets etc. Mostly it was when it was really cold out and they couldn't open any doors or vents.
I have designed a CO2 generator, I even made a post about it here. See this link please: http://www.gardenstew.com/viewtopic.php ... highlight= I am currently in the process of building it, as I really want to experiment with aquatic plants - Mainly Algae, as I want to explore the possibility of making Bio-Diesel from extracted Algae oil... I have already experimented with making Bio-Diesel too. Please see this thread that I started here some time ago: http://www.gardenstew.com/viewtopic.php ... =biodiesel Anyway the generator that I am making now has the option to give CO2 to other ordinary plants as well (aside from aquatic plants and Algae). So if you are really interested in making such a contraption, then I will gladly share my designs with you.
