In cannabis growth, as with any other plant, the relative humidity is used. It is also worth noting that humidity and temperature are interrelated. The amount of water vapor that air in an area can hold increases with increasing temperature.
Watering cannabis plants in a grow tent increases the plant’s water intake through the roots. High uptake of water by the plant increases the water loss rate through the leaves, making the room more humid. The induced moist environment, in turn, regulates the respiration process keeping the marijuana plant healthy. Again, watering should be optimized to maintain the grow tent in the recommended level of humidity.
In conclusion, it can be said that humidity is an essential condition in the growth of cannabis plants. Always start with a high relative humidity of about 70% for your cannabis seedlings and reduce the moisture gradually until the plant is ready for harvest, where the humidity should be around 40%.
Bigger grow light – Get a bigger grow light to produce more heat within the grow space (and get plants to grow faster!)
Optimal Humidity is 70% RH
Mold is especially dangerous in the flowering stage because it can form on or inside your buds or colas without you knowing. If you find that you have mold growing in any of your buds, or buds are rotting from the inside, you should immediately throw all of the contaminated buds away. Bud rot can ruin entire harvests, so if one bud is infected thoroughly search your grow room for more. If you can’t lower the humidity and already have a rampant mold problem, the best choice might be to cut your losses and harvest immediately to avoid any other buds getting bud rot.
40-60% RH (if you see wet spots forming on the leaves, humidity is too high or you need to increase air circulation). Beware of white powdery mold in humid grow spaces!
Since humidity changes how much water your plants drink, and the water you give your plants have nutrients in them, being in control of humidity gives you increased control over your plant’s nutrient intake.
Okay, so now you know why you need to manage humidity when growing cannabis, but you may not know what humidity you are aiming for. This chart is the quick-and-easy answer:
Install TeamViewer (it’s free for personal use) or you can also use Windows Remote Assistance (not as user friendly in the beginning, but a good choice).
Humidifier – will add additional moisture to the air, I like the evaporative type of humidifier because it also works to cool down temps slightly. Make sure you get a humidifier with a large holding tank (holds at least 6 gallons of water at a time). Those “one-room” humdifiers with a 1.5 gallon tank often need to be refilled several times a day.