So you wanna grow some weed?

Jesselikes2grow

Master Builder
So you want to grow your own pot? Get a light, put seeds in some dirt and you've got some super dank in a week or two right? Hahaha

NOPE.

Environment Imho is the second biggest factor in your ability to grow these plants, with genetics being the first factor.
Genetics give you the potential for a great plant, but its the environment that enables it to reach that level. Putting a basic plan together with your growing goals in mind will save you time, money and headaches with your grow room design and setup.

Lights:
Your light is like the engine of the grow room that drives it all.
Led, hps, cmh, whatever, they can all grow some great weed. They all have benefits and drawbacks to each type of lighting. Biggest thing is selecting the appropriate size for your grow and tailoring it to work with everything else. IE: Proper venting for hot lights, tent/room size and or height limitations to name a couple. A good guesstimate for what is needed is 25 to 35 watts per ft vegetative growth, and 30 to 50 watts per ft in flowering. A large variance I know right, so many different lights with various efficiencies to choose from. Going into all the details of lighting is a rabbit hole to go down in another conversation. Lol. Keep it simple for now, can always upgrade later. Just pick a light that fits your budget, your space and future growing goals. Lol

Ventilation:

Just like you and I plants need to breathe. A good ventilation system is paramount for plant health and growth. Exception being if Co2 is being used in a sealed room with humidity controls etc, again, that's another rabbit hole for another conversation. Lol we're keeping it simple here right now. Lol
Your grow room should have an air exchange rate of about 8 to 10 times per hour on average as a baseline. Hot lights or humid conditions probably want more airflow exchange. Always get a bigger fan than needed with a speed controller, you may need more airflow later on and a filter will slow airflow down hence the bigger fan. A bigger fan on low speed is much quieter than a small one at full blast fyi.
Here's a formula as a baseline to begin with. length×width×height of room = cubic ft of room.
Divide that by 7.5 and you'll have your minimum cfm required for a 8x/hr air change. Ie: a 4x4x8= 128 cubic ft of grow room. 128÷7.5=17.06 cfm fan needed for said room at 8x per hr.
10x per hour would be about 22 cfm.

Air filter:

Good odor control should be incorporated into the fan setup. Activated Carbon filters do a great job when sized for the area and connected to the fan setup. Size filter flow rates to the cfm rating of fan and you'll be good to go.
Even if your in a legal state, do you really want to let everyone know about it? Have some teenager break in cuz he smelled your crop? Better safe than sorry.

Temperature and humidity:

Plants love the warm weather, mmj in particular. Keep low temps above 65* and high temps below 90* optimally. Cold regions may want to add an oil filled rad heater, no fans, very efficient. Or a small ac unit in your hot climates.

RH is another big factor. A humidifier/dehumidifier can make a big difference to your grow if RH is an issue in your climate. Stay above 40% and below 60% as a max and minimum guideline. Veg wants a bit higher RH, and flower less. It is directly associated with temperature. The higher the temps, the higher the RH can be. The lower the temps the lower the RH should be. Here's a vpd chart as a reference.
vpd_2degree.gif

Those are some good basics to begin with, I'll add some more when ive more time.
Once the basics are covered maybe we'll venture down a few rabbit holes together. Haha.
 
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JWM2

Member
Great thread. This should help folks get dialed in.

One product that I was skeptical at first but fully believe in now is the Pulse One VPD monitor. Sure you can take temps and RH and cross reference a chart but to be able to read the VPD just by looking at your phone is huge imo. I thought my VPD was spot on, then I got a pulse one and realized I was just a little off. Made the proper adjustments and viola I’m back in the zone. It really opened my eyes that a little technology can go a long ways in your garden.

Environment is often the most overlooked aspect of indoor growing. I’ve been saying it for years. Back in the day we thought the drier the better. Now we know there is an ideal range and if you stray too far above or below then your grow will suffer.
 
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