Climate Control

[LetsGetHigh33]

Hey fellow growers a wee topic here

i am about 4 and a half weeks into flowering in my first grow, temperatures reach around or just below 30 degrees celscius.

Recently it's been high temps outside which has been making my grow tent rise to around 34 degrees. I have 2x600w dimmable ballasts so I have been dimming them temporarily on hot days down to 400 to help lower the temps a bit.

Will this effect how buds will develop?????

I've only done this 2 or 3 times to keep my temps down as it was going above 30 mark. Some days I've just left it sitting at 30+ cel.

i have ordered a 6 inch intake fan so i can bring cool air in to bring my temps down a lot further just waiting on delivery

also humidity

my humidity is around 40%-45% when lights are on but at night it will raise to 72% max when lights are off

should I invest in a de-humidifier for using when the lights go off to keep humidity down at night????

or only in the last 3 weeks of harvest??

[Sheesh]

30 is a little high unless you are using CO2. 72%RH during flower is risky as mold powdery mildew or mold can set in. Is your exhaust strong and venting outside or at least outside your grow area? Good exhaust and bringing in cool air can help heat and humidity. Make sure you have plenty of airflow and lollipop / defoliate if needed for good airflow. Try to keep temps below 27 and humidity below 50 in flower. In flower, the goal should be around 25 temp and 40% RH. So, use airflow, cool air supply and dehumidifier if you have to. A dehumidifier will add heat so try to keep that heat away from your grow too.

[Garcon]

Hello lgh33. I had the same issue and posted the topic Heat or Humility just last week. Fellow growers here helped me decide what to do. Tuff time of the year to finish a grow. I have a larg dehumidifier far away in the large room that my intake comes from. The RH is low and the intake is dry, but Mutch warmer. @ 8• Fahrenheit warmer. My efforts to decrease heat raised my RH. Long story. However I decided to deal with the higher temps rather than higher humidity. Plants are health so I did some more defoliation and increased my air circulation by adding additional small fans. It may be better to have air flow low under your canopy of buds and just above your soil/ medium as well as above your plants. Also it might help to water your girls early when your lights are on to allow plenty of time for soil surface to aerate or evaporate a bit before your lights go out. Oh. Also you could consider changing your light schedule for your lights to be off during the hot time of the day might help. I considered changing my schedule but didn't for other reason tho. Either way if you can tap things down just a tad, you should be ok. I hope my words will help you dial it in. Good luck and have fun. Garcon🍁

[Beach_Town_Brit]

Hi GetHigh
I agree with Garcon, in my experience high temps will do more damage than humidity as long as you have constant air flow and movement to help combat mold. (this said, I live in a generally dry climate).

As to how far you can go with temps, I let my tent hit a max of 90F (32C) and try to keep my typical "day" temp in the mid 80sF (30C'ish). This seems to work for me but I am under LEDs and there's some argument that plants under LEDs can thrive at higher temperatures than plants under HPS (https://www.blackdogled.com/blog/lst/).
Keep in mind that it's leaf surface temperature that's important rather than ambient temperature.

[D.A.A.S.69]

Hello 33 You've just got some excellent advice from all 3 answers above.Like Garcon said above , tuff time off the year. I live down south and it's been extremely hot here . It's a fight but I believe you will win it ,just try to stay on top of it like you are doing. Good Luck 33 PS BeachTownBrit you have an awesome journal

[LetsGetHigh33]

Thanks some great advice there guys