High levels of carbon dioxide (C02) are bad for humans and the earth’s atmosphere, but great for marijuana plants. That’s why marijuana growers add C02 into their indoor grow rooms.
But are we adding C02 the right way, so our marijuana plants grow faster and give us fatter yields?
To start with, let’s remember why C02 is so important: our marijuana plants inhale C02 and use it as fuel for photosynthesis.
In nature outdoors, there’s nearly 400 parts per million (ppm) of C02, and that amount is adequate for plants.
But in a closed-up grow room with vigorously-growing plants, your marijuana plants might use up much of the C02 during lights-on cycle.
The plants’ growth slows as C02 levels drop.
You add C02 to your indoor grow room to make up for what your plants use, and to increase their growth and yield.
Photosynthesis is a primary driver of your marijuana plants’ metabolism.
It happens only when light is streaming onto your marijuana plants.
That’s why C02 augmentation is done only during lights-on hours, not during dark hours.
You deliver added C02 using tank C02, fermentation/bacterial reaction C02, chemical reaction C02, C02 generators/burners that use propane or natural gas, and dry ice.
Some of these are simple methods, such as combining vinegar with baking soda, using bucket C02, a beer-making kit, a block of dry ice, or similar low-tech solutions that make it very difficult to precisely control the amount of C02 generated.
Most professional cannabis growers have found that using bucket C02 and similar techniques doesn’t provide adequate C02 increases.
C02 distribution control is important in your marijuana grow room, but doesn’t just involve controlling the C02 parts per million (ppm) in your marijuana growing environment.
To get the most benefits from added C02, you control, adjust, and balance grow environment temperature, light intensity, water delivery, humidity, and C02 levels so they are optimized together.
You have to adjust the parts per million and quality of your hydroponics nutrients.
That’s because adding C02 revs up your plants so they want more water, light, and nutrients.
If you give them extra C02 without also giving them optimized levels of water, light, vapor pressure deficit, and nutrients, the added C02 is mostly wasted.
It could even be considered detrimental to your plants, because the extra C02 increases marijuana plant metabolism, but the marijuana grower hasn’t increased all the inputs necessary to fuel the plants’ stimulated metabolism.
For ultimate C02 control, marijuana growers use tank or burner C02, and they monitor and adjust C02 parts per million using C02 monitors and ancillary regulating equipment.
They’re aiming for 1200-1600 ppm C02 during lights-on cycle, depending on the age of the plants and other conditions.
Added C02 gives you the benefit of being able to run a hotter than usual grow room, which saves money on air conditioning and other heat-handling costs.
Regular grow room optimal temperature of 74 degrees Fahrenheit can be allowed to rise to 80-85F in a C02-augmented environment.
Just what good does added C02 do for your marijuana?
Because it stimulates photosynthesis and metabolism, it creates increased growth rate, earlier maturing crops, increased potency, and heavier harvest weight…but only if you increase and balance other inputs: light intensity, water, nutrition, grow room humidity, temperature.
If you have an under-lit garden, inferior hydroponics nutrients, too-low nutrient ppm, a too-cold grow room, or you’re not providing enough water to your marijuana plants, the extra C02 could do more harm than good.
You adjust your growing calendar when you add C02 because your plants speed up so you get to bloom phase earlier, and it finishes faster.
This gives you more crops per year…meaning more pounds of fine marijuana!
I give my marijuana plants an increased base nutrients ppm, along with special additives like Bud Ignitor, Bud Candy, Bud Factor X, B-52, Big Bud, and Overdrive during bloom phase.
These hydroponics nutrients products work with added C02 to increase growth rate, bud size, and finishing.
Providing this kind of full package of optimized nutrition gives your hydroponics cannabis plants the foundation they need so the added C02 is most beneficial for your marijuana.
Marijuana growers should start adding C02 when your marijuana seedlings or clones are well-rooted and into their third week of grow phase.
You want the added C02 to go into the plant canopy, and stay in the canopy as long as possible.
Marijuana growers achieve this by adjusting fans and venting (including adjusting their angle, pitch, aeration strength and timing), and by using small-diameter tubing to channel C02 directly into the marijuana leaf zone.
My C02 hardware is a C02 tank, regulator, flow rate valve, C02 sensor, automatic shutoff apparatus, and a monitor that coordinates C02 disbursement and venting.
For a professional rig including the equipment I just mentioned, you pay about $1100.
It’s easy to use and run.
The only hassle is getting the tank refilled.
My second favorite C02 for marijuana apparatus is a C02 burner, but they create heat, humidity, and safety problems, and you have to source and use propane or natural gas.
Only you can decide if these drawbacks are worth it in your marijuana garden.
Marijuana growers running small closets, grow tents, grow chambers or other small-space grows can get away with using C02 bucket systems, dry ice, and other low-tech methods, but those aren’t optimum methods.
I highly recommend tank and regulator, or C02 burner/generator, whenever you can use them.
Please remember: it’s not healthy to spend time in your marijuana grow room when C02 levels are elevated.
Breathing 1400 ppm C02 is not good for you!
Adding C02 to your marijuana grow room is relatively easy, and it gives you faster-growing plants, more THC, and heavier yields.
The cost of investing in professional hydroponics marijuana C02 equipment pays itself off in a few crop cycles, and after that, you continue to get more buds faster from every crop cycle, almost for free!
Marijuana growers should also read this important article about dangers of using too much C02 in your grow room.