From the CO2Science archive: What’s up doc? CO2 is, and so, apparently are carrots. Formally known as Daucus carota L. var. sativus this hardy vegetable was subjected to an additional 300 ppm CO2 in 5 experiments between 1987 and 2008. The mean increase in plant dry weight was 77.8% with the best results occurring at high temperatures. So toss them into your stew this winter and thank CO2 that they are growing better than ever.