Learn how to Grow Your Four Legal Cannabis plants today!

Getting The Temperature Right

Before we get into the details of setting up your own amazing watering system, a few reminders to put your new grow into perspective: First, cannabis plants love a little more heat and humidity than people do. The ideal ambient air temperature inside a cannabis grow operation should be between 75 and 80°F (24 and 27°C). The ideal relative humidity level to maintain for your cannabis plants in the vegetative cycle is between 40 and 60%.

When you visit your plants daily, take advantage of the Control Unit you’ve conveniently hung on the inside wall of your new growing area. This handy digital device will show you the temperature, relative humidity level and time of day with a thermometer, hygrometer and a clock respectively.

 During your plant’s “day time”, the Control Unit will show you the exact temperature and humidity level inside your tent or grow room. At this early stage of your young plants’ development, maintaining the correct temperature and humidity inside your grow area should be “automatic”, especially if you have an LED grow light which burns much cooler than conventional lamps.

It’s when your plants begin to mature and grow beyond 1 foot in height that their transpiration and photosynthesis ramps up, putting significantly more heat and moisture into your growing area. Remember, your plants only use 5% of the water they take up through their roots as they draw the nutrients out of the water. The other 95% of the water gets pumped out back into your grow room air through the plant leaves. 


If the temperature and humidity are a little too high however, you need only turn down the heat in the growing area. This can be as easy as speeding up your ventilation system. If you’ve purchased “one-speed” input and exhaust fans, simply turn down the temperature of the main area or room that your grow tent or grow area is situated within. If that’s not possible, open a window. If it’s hot outside, put an air conditioner in that window. 

If neither of these options work for you, and if your residence does not have central air, then you can get a little “portable” air conditioner just for your growing area. Even though a portable will use extra power, it pays for itself by doing “double duty”. It will control the air temperature and work as a dehumidifier by removing excess humidity from your grow room air. And the water it collects is actually distilled pure water that you can add to your large main reservoir!

The second point you must consider is something experienced home growers argue about endlessly: Where to put the vented moist, warm air? Practically speaking, a little grow tent can have its air vented directly into the outer room without causing any mold damage if and only IF you can control the outer room temperature. 

To keep things as simple as possible however, we recommend that you never, EVER exhaust the air from your growing area into another room and especially into a basement or an attic if you have one. Forcing your exhaust air into another room, an attic or basement will leave you open to the possibility of damaging your residence with mold. Mold is both a serious health hazard and can be VERY expensive and sometimes even impossible to get rid of—without gutting your entire residence! Growers should NOT take this risk.

Forcing your exhaust air into another room with no windows, temperature controls or dehumidification will only increase the temperature and humidity inside of your living area which ultimately recirculates BACK INTO YOUR GROWING AREA!

So take advantage of some duct line (like the wide exhaust hose that’s hooked up to your dryer) and vent your growing air out of your growing area and completely OUT of your residence. Doing so will give your plants a healthy stable growing environment at the ideal temperature and humidity they can thrive in!  All you need to keep adding after that, is the love…AND the water!

This is why getting your water and nutrient delivery system figured out while your plants are still small is so important! We’ll be covering this in an upcoming 

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