Raising your yields in your indoor grow by up to 20% might sound like a complicated task with a lot of steps.
But it's actually as simple as just adding some CO2 to your grow!
Your plants need CO2 as part of the process of making energy from light via photosynthesis. Without CO2 your plants will “suffocate” and die. That’s part of why it’s so important for your plants to get plenty of fresh air.
For growers using lower-powered grow lights like CFLs or fluorescent T5 fixtures, there’s often more than enough CO2 in regular fresh air for your plants to be able to process all the light they’re being given.
But things are different when there’s more light being provided than your cannabis plant can naturally use.
Supplementing CO2
In stronger light situations using HPS, CMH or LED lights, supplying more CO2 allows your plants use more of that light, resulting in increased photosynthesis. By getting your plants to produce more energy from the same amount of light, they’ll reward you with faster growth and bigger yields.
Supplementing with CO2 in this way also makes your plants more resistant to heat and light stress, which is an added bonus.
Unfortunately, supplementing with CO2 can be expensive. So before you start adding CO2 it’s a good idea to figure out how much, if any, you should be providing to get faster growth.
Benefits of Adding Extra CO2
If you’ve maxed out the other limiting factors (especially light), CO2 can make your plants grow up to 20% faster, produce bigger plants, and enhance your yields.
Also, maintaining 1200-1500 PPM of CO2 in the grow area allows growers to keep temperatures much higher than normal, up to 95°F (30°C). For growers with hot bright lights, this can make it easier to keep temps at a range their plants will like.
Lastly, CO2 enrichment can be beneficial for security if you seal your grow room since you’re not venting out smelly air. Certain methods of adding CO2 like using a CO2 generator will also create natural smells that help cover up the smell of of your plants directly.
Disadvantages of Adding Extra CO2
CO2 isn't nearly as effective if you don't have brighter lights. You probably need either MH/HPS or strong LED grow lights to produce bright enough light for your plant to be able to use the extra CO2. CFLs and T5s probably aren’t bright enough to get great results.
Although adding just a little CO2 doesn’t require a sealed room, when trying to maintain very high levels of CO2 (like 1200-1500 PPM) you will likely need to seal up your grow area in order to prevent CO2 from leaking out.
When it comes to cost, it can be expensive to get started if you want to inject a whole lot of CO2 into your grow area, for example in big grow operations.
The cheapest ways of adding CO2 are actually not very good at providing a lot of CO2 over time. However they can be a great way to “dip your feet” and try CO2 out.
The best CO2 setups in the long run are a bit more pricey to get started with, though they become a lot cheaper once you’ve got your initial supplies.
Optimize Your Grow for CO2
CO2 supplementation works best when everything else in the grow space has already been optimized. For most growers, a little optimization may result in even bigger returns on yields than adding CO2!
But with both optimization and supplemental CO2 together you can see an incredible boost in yields, plant health and quality.