Temperature Fluctuations, Need your input!!

For the most part of my vegetative cycle, the temps never rose above about 86, with average temps in the 70's.

Now I'm 6 weeks into flowering with some sativa-dominant HSO Blue Dreams.

I just added a 600 watt light into my 4x8x6.5' grow tent, where a 1000 watter was previously keeping the temps perfect.


Now I was having problems with temps getting to sometimes 61 at night, but typically just fluctuated between 65 and 80 with lights on, and lights off. Temps were usually room temp when I checked it.

When I added the 600 watt light a day ago, temps were perfect for an entire night and day, but it seems the temps have fluctuated outside the building from being 19 degrees Fahrenheit during the night, to now 30 degrees, but I'm pretty sure this is just temporary, and it will dip back down, but it definitely shouldn't get any hotter.

If temps temporarily reach at MOST 86, but are consistent at 86 during lights on, for only lets say a few days, then will it really affect yield or potency? I'm buying a fan twice as powerful for my carbon filter, and a booster to add to the light, as well as a booster to pump air INTO the tent. So, I'm hoping those issues will be resolved. I also have HELLA fans INSIDE the tent to circulate things. The temps reach a max of 84 at the start of a canopy, and at the top, 86.

But, should I really worry about losing weight and potency if the temps occasionally rise to 86 for a few days every now and then during flowering, or am I just a worry wort?

Thanks guys! I'll do a few dabs while I await some answers

yes high temps for a few days can have an adverse effect, imo more likely a couple pollen sacks than a potency decrease..yield decrease possibly.. so just do what you can to keep it down...i would shut down the 600 until the problem is solved..

I run my lights at night for the heat reason, but my lows are down sometimes to 60 with lights off, but since I am up for most of the on cycle, I try to vent as necessary to keep my on temp to 80 max, but that is my top thermometer, which is just a hair above light level (CFL's), and I have another thermometer at floor level, and that usually stays at 60-65, with the one on top of my pot about the same.

High temps suck buds out. I grow like crazy in winter free a/c . Find a way to route a dryer vent outdoors (crawlspace/attic)attach a fart fan to it with extension cord to hot area put a cheap thermostatic power switch on it adjust for quality and done. Might just double yield.

i think your a worry wart but lowering the temps definatly wouldnt hurt.

mid 70's is ideal.

dropping temps at night i dont think is a big deal, i have had some serious temp fluxuations in my outdoor grows and never seemed to phase the plants. 70's during the day and down to 30's at night

My grow space gets to low to mid 80s with the lights on and the doors closed with no fans on and down to mid 70s at night with lights off. I try to vent the closet in the day but this does not always happen. So far I have had no issues plants seem happy.

Try a grow that doesn't hit 76 with familiar strains and a program you feel is exceptional then make the call. If your good at what you do this knowledge skyrockets quality,quantity and some other q word. I always considered Ca outdoors as pretty top notch, so high temps seemed irrelevant when summer avgs top 95. I think added time and conditioning to seasonal changes help.

Yeah, Idk they are looking pretty good and they've got another 2-4 weeks until I can chop them up, but I wanted to add that light in there to really increase yield, so if I shut off the light wouldn't that hurt yield even more?

Here's some pics:

You have 1600 watts runnin? Idk dude if two lights are too hot and one is controlled take logical action. I'm used to major fluctuations as well but cold has never concerned me just slows things a bit. Your not going to notice dramatic damage at all. I'm just on this cold budding thing probably because I can. Heat out top cold in bottom. I can't reread this anymore .

herbbilly said:

You have 1600 watts runnin? Idk dude if two lights are too hot and one is controlled take logical action. I'm used to major fluctuations as well but cold has never concerned me just slows things a bit. Your not going to notice dramatic damage at all. I'm just on this cold budding thing probably because I can. Heat out top cold in bottom. I can't reread this anymore .

Click to expand...

Yeah I forgot to mention that the cooltube 600 watter I added is an HPS, and in the pic you only see a 200 watt T5. That picture was a few days old.

And yeah, this is my first grow, and I want to try to do everything perfect, and I'd rather make a fool of myself asking too many questions here on rollitup then to see my babies go to shit or not live up to their full potential. But yeah what do you mean by you cant reread this anymore?

herbbilly said:

Try a grow that doesn't hit 76 with familiar strains and a program you feel is exceptional then make the call. If your good at what you do this knowledge skyrockets quality,quantity and some other q word. I always considered Ca outdoors as pretty top notch, so high temps seemed irrelevant when summer avgs top 95. I think added time and conditioning to seasonal changes help.

Click to expand...

people always make the assumption that oh because it gets to 100 degrees outside i can run and hit 100 inside and it will be fine....no sorry not the way it works. its not just about temperature its about the intensity of the temperature and the humidity and little things come into play like the fact that outside you may have shade here and there. 86 wont harm a plant especially if its only a few days but if i see my temps get past 80-82 i take measures to make sure it doesnt happen again. these temperatures over a long period of time or in conjunction with a dry room will cause adverse effects even if you dont see them and if your hitting 88 or in the 90s at times your bound to have bigger problems.