Greetings,
This following was posted by me as part of a larger thread in the room design section, but I am very curious about this and it fits better in this section anyway.
My partner has a master's degree in plant science. When I spoke to her about the conventional wisdom that 1500ppm co2 is ideal, she asked what proof I had to back up this claim. I realized that I have no actual proof. I have never used co2 and have only heard anecdotal evidence, though lots of it. Many people claim yield increases but I cannot find any grow logs showing side by side grows where the only variable is co2 added in one space, none added in the other. Everyone claims 1500ppm adds 20-30% to final yield, but non-anecdotal proof seems lacking. I recognize that there is a lot of anecdotal evidence, but how much of this is the placebo effect combined with growers paying extra close attention to all details, thus boosting yield.
My partner has access to all scientific journals and researched the issue. There are numerous studies on the effects of co2 that are not anecdotal. For C3 plants like cannabis, science tells us that adding co2 has a substantial positive vegetative effect, increasing leaf and stalk growth rate and size. In the flowering stage though (once flowers start to form), added co2 has a neutral to negative effect. In other words: great for veg, bad for bloom. In other other words: it is possible that any increase in overall yield has to do with creating bigger, healther plants in veg that then finish bigger, as opposed to co2 having a positive effect in bloom.
A few questions:
1. Do you know of any scientific studies that state adding co2 is beneficial to the flowering stage of C3 plants?
2. Do you know of any grows that have done a side by side study of increased co2 vs no added co2 in bloom?
3. Have you used co2 exclusively in veg (not in bloom)? What were your results?
Thanks!
This following was posted by me as part of a larger thread in the room design section, but I am very curious about this and it fits better in this section anyway.
My partner has a master's degree in plant science. When I spoke to her about the conventional wisdom that 1500ppm co2 is ideal, she asked what proof I had to back up this claim. I realized that I have no actual proof. I have never used co2 and have only heard anecdotal evidence, though lots of it. Many people claim yield increases but I cannot find any grow logs showing side by side grows where the only variable is co2 added in one space, none added in the other. Everyone claims 1500ppm adds 20-30% to final yield, but non-anecdotal proof seems lacking. I recognize that there is a lot of anecdotal evidence, but how much of this is the placebo effect combined with growers paying extra close attention to all details, thus boosting yield.
My partner has access to all scientific journals and researched the issue. There are numerous studies on the effects of co2 that are not anecdotal. For C3 plants like cannabis, science tells us that adding co2 has a substantial positive vegetative effect, increasing leaf and stalk growth rate and size. In the flowering stage though (once flowers start to form), added co2 has a neutral to negative effect. In other words: great for veg, bad for bloom. In other other words: it is possible that any increase in overall yield has to do with creating bigger, healther plants in veg that then finish bigger, as opposed to co2 having a positive effect in bloom.
A few questions:
1. Do you know of any scientific studies that state adding co2 is beneficial to the flowering stage of C3 plants?
2. Do you know of any grows that have done a side by side study of increased co2 vs no added co2 in bloom?
3. Have you used co2 exclusively in veg (not in bloom)? What were your results?
Thanks!