Heat stress in flowering

On day 3 of flower nearly day 4, my 12/12 is light on during midnight to midday and off midday to midnight. I am getting quiet high temps(88c) during the day even with the light off. Should I be worried about my plant? Is this going to cause issues during flower and if so how can I fix this where I live gets hot during the day and the room the tent is in gets quiet hot (no where else to put it)

88F is high and at the upper limit. You can mitigate temps by increasing airflow in the grow space. If you have a light with a detached ballast you can put the ballast outside of your tent or grow space and that can help too.


I have two fans in there at the moment one clip on 10 inch fan and a tower fan both oscillating should I add more?

Should I open more of the passive airflow holes at the bottom I only have one open at the moment


@Danielsan22 Yes, also adding a couple of frozen water bottles placed in front of the fans air flow, will allow for cooler air blowing across your space ( also increases RH by about 3-4% in your warmer environment).

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If your RH is not affected by opening a vent or cracking the tent door open some could help, sometimes I’ll put a small fan facing the vents to push some of the heat out. With photos on a 12/12 schedule, you’ll have to be careful with light leaks during dark hours. You don’t want to end up with a bunch of Bruce Jenners :love_you_gesture:


It’s a battle at the moment it’s either temp high low RH or high RH low temp it’s frustrating

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I know that struggle. Same for me doing daily adjustments in environmental conditioning :love_you_gesture:


I8c is 190.4 in Fahrenheit. I think plants would be cooked at this temps lol

18c is actually 64.5 F

My bad his post said 88c not 18 lol

Gonna die walking into the tent lol


Because you got your lights on in the middle of the day. Turn lights on Dusk till dawn 6 to 6 eliminates this problem

Am I able to change this now flowering stage has already begun?

Give it a full day (24hrs) of darkness. Then began your light schedule. The 24 hour darkness will do nothing but increase trichome production. (Water 4-8 hours before flipping to 24 hr darkness; medium levels of phosphorus and potassium, low level of nitrogen.)

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I agree, as I would rather chance it than risk high heat and loose airy buds.

Roger that mate lights on until 6 am (it’s midnight now) after that light is off for 24 hours and it will come back on at dusk in 24 hours or maybe a little more then 24 hours

A little more will not hurt. Rather go more than less.

From there I’ll start 6pm to 6am lights on and 6am to 6pm lights off

Remember, in flower, lights make you grow, the dark makes you show.