There would likely need to be multiple studies done on a large scale, but on the small scale we could look at something like this:
Null Hypothesis – Elevated CO2 levels during flowering do not affect cannabis buds.
Procedure – Using same strain (IE Blue Dream), create (at least) 3 groups to be tested:
- Control group (No CO2)
- Elevated CO2 during first 4 weeks
- Elevated CO2 during entirety of flowering
- If you want to take an extra step and make it super interesting, add a fourth group that only elevates CO2 after the first four weeks are up.
Pre-measure plant and pot mass, record and measure all nutrients added or flushed (measure the effluent). Record amount of water added per plant. The same lighting, growing, harvesting and curing techniques should be followed (all ideally in the same environment). In the event of pest infestation, results for said plant should be thrown out.
Data to collect:
- Biomass of wet buds post-harvest
- Biomass of dried buds post-harvest
- Adjusted index of biomass (based on initial weight, inputs, etc) by group
- Total cannabinoid content by group (adjusted for total number of plants, should any be tossed out)
- Total terpenoid content by group (adjusted for total number of plants, should any be tossed out)
I’d recommend that each group contains at least 50 plants, ideally 100 or more.
The final analysis could compare the control group against the experimental groups, as well as the experimental groups against each other. I doubt the null hypothesis would hold, but it would be interesting to see how different groups 2 thru 4 are.