Dear Dan, I’m planning to have 10 plants in a 12’×12′ room, what would be the ideal temperature to try and maintain? Does the temp remain the same during vegetative and flowering periods? – Terry in SC
“Daytime” air temperature (meaning when your lights are on) in your growroom should be kept between 68-78°F. They will tolerate up to 80° or so but any higher and growth rates dwindle. Plants that are supplemented with CO2 gas as well as clones and seedlings can withstand slightly higher temps as well.
Temperature while the lights are off should be kept at 60-70°F. Keep in mind that the air temperature at leaf level can be considerably higher than the rest of the room. At the least, get a digital thermometer that records highs and lows in its memory so you know what’s going on when you’re not there. Avoid large day/night fluctuations of more than 10-15 degrees either way and maintain as consistent and environment as possible for utmost success.
Don’t miss our previous Grow Q&A: Why Are My Cannabis Clones Moldy?