There has been a debate raging for years between those who have ventilated their indoor gardens to the outside, using Mother Nature for cooling, humidity control and CO2 replenishment… and an increasing number of self described control freaks who insist on controlling every aspect of their little worlds, even to the point of sealing them off from the outside world completely so as to better manage their growing conditions.
This month, I’ll explore the pros and cons of each approach, and then turn it over to you, dear growers, to continue this debate and advance the science of indoor gardening for everyone!
One of the biggest justifications of ventilating a grow room to the outside- be that the great outdoors, or at least the rest of the house- is its simplicity. At least for smaller setups with less than perhaps 4000 watts of lighting, this approach basically requires only some fans and intelligent airflow management. As long as you can keep the temperature in your grow room down to a manageable level, you’re golden with this style of gardening- as long as you’re not too particular about humidity levels, or maintaining higher than ambient levels of carbon dioxide. Therein lies the rub, however- since you can’t control every parameter to the highest degree, you will have a tough time pushing your garden to produce the really high yields you hear about. Another serious problem is infestation. Bugs, moulds and mildews can seriously diminish the results of your hard work, and possibly even cost you your crop entirely! This is a constant struggle for as long as the door remains open, so control and prevention are the constant watchwords for a garden like this one.
To steal a phrase, sealed grow rooms can be fairly summed up this way; “Ultimate Power!!! …eensie weensie living space.” The challenge and opportunity of this approach is that you’re in total control of all aspects of your plants’ environment, and therefore it’s up to you to effectively manage every detail. Seal the room, and you can bet the first thing you’ll notice is rising temperatures. Okay, install that air conditioning! Oops, now your humidity is going through the roof! Get a dehumidifier! Hey, where did all the CO2 go? Time to put in a CO2 enrichment system! If I’m spending all my time watching things, when do I SLEEP?? Queue up the environmental control unit! And my favorite; holy cow, look at my electric bill! Now that you’ve seen Mother Nature’s job, are you sure you really want it? It’s a lot of work! And don’t forget- the only place infestations spread faster than in a ventilated grow room is… yep, you guessed it- a sealed one, where the conditions are always perfect for maximum exponential growth!
So why would anyone want all that brain damage, you ask? Welllll… once you finally get the thing dialed in, you can push your plants to achieve growth rates radically faster and more bountiful than anything you’re likely to see outside. Ever. Better still, once you have the room set up it’s going to stay that way, crop after crop, allowing you to do it consistently, time after time, come hail or high summer. Consistency is the mother of repeatable results, and if you can effectively control every aspect of your grow, you too can harness its power. Better still, since sealing your grow room means reducing the ways pests can get in, you’ll be able to use much less intervention, less often to maintain a bug and mildew free environment- and that translates directly into better taste, better for you, for a lot less effort and cost.
Growing in a sealed environment is more different than you might think, too- your plants will be able and willing to use more of just about all inputs from light to nutrients and CO2, faster, because the limiting factors have been removed- it’s like the difference between driving your Corvette on the street and track day, where you get to let it all hang out and see what she’ll really do! Sealed rooms can be done in small spaces, even as small as just one hood and a window unit AC, and the bigger commercial indoor environments are almost all sealed controlled environment style. The main hurdle is cost- count on steep electric bills to cool all the gear you install, plus extra equipment to manage all the other factors of the environment the great outdoors used to do- however imperfectly- for you.