93 degrees, too hot?

paOol

Member
im doing the 2 rubbermaid setup and i have 2 exhaust fans up top and 2 intakes on the bottom.

getting about 93 degrees for the temperature and 35% humidity ( i realize thats pretty low)

will the temperature be alright to grow in?
 

assasinofyouth420

Well-Known Member
Ive heard a lot of people can grow in 93. A lot has to do with the strain you are growing. The general consensus seems to be at least below 85. CO2 could help. Got any pics?
 

tranquility

Active Member
no you will fry your plants...you want the temps in between 70-80 degrees. id say 75-80 is ideal depending on the strain. if you can get it down to about 82 or less you should be fine as long as it doesn't fluctuate a whole lot.
peace&pot
 

headshots420

Well-Known Member
it's recommended to keep temps in the 70's but mid 80's is fine. once you hit 90 degrees indoors you begin to slow growth. Some people will give you the argument that outdoor temps in cali commonly reach the high 90's so indoor temps that high are fine, this is incorrect. Try bringing the room temps down but if this is not possible you can freeze water bottles and place them in your water res to give the plants an adequate cooling. You can also introduce co2 into the environment to help compensate for higher temps. Hope this helped.
 

paOol

Member
hrmm, well i measured the temperatures while the thermometer was on the top rubbermaid, i'll place it on the lower level and see if it differs
 
You should be taking temps at the canopy level or the tops of the plants.
This is true.

More CO2 Will not solve the problem nor will it hurt you in any case here. However if the plants are too warm more CO2 will be wasted since the plant will be using it's stoma to transpire which cools the plant. The reason you do not want your plant to get too warm is that the stoma is used to exchange gases and in this plant is primarily located on the underside of the leaves. This is where the plant will exchange water inside the plant as gas for CO2 and other parts of the air outside the plant.

So basically when your plant gets hot it sweats, dry air increases the effectivness of that sweating (transpiration).
Things to consider is that the warmer it is the faster the cycles will be carried out inside the plant as far as ATP and sugar production. However it comes to a point where you are getting TOO warm and the plant needs to cool itself down, if it devotes too many of it's stoma to transpiration it will not be bringing in as much CO2 (and other gases) which will be bringing ATP and sugar production to a crawl.

So at 93 with 35% you are probably fine to survive the whole lifespan, but will they be as good as they could? I really don't know enough to answer. I know how plants work inside but I havent done any extensive research myself on temperature, perhaps looking for a real case study on tomatoes may be a valid option. Too bad the US doesn't grant research for MJ.
 

Serapis

Well-Known Member
We grow weed down here in damn near 100 degree days.... My grow room hits 90 at times. I'm not concerned. lights off it gets in the mid 70's

Seems like a perfect spread of temps...
 

paOol

Member
the bottom level was only 1 degree cooler =\.
i dont know why my temps are so high, im running 6 42watt CFLs.

i don't know what else i can do to drop the temps
 

TaoWolf

Active Member
I'd definitely start adding chilled/frozen water bottles to the reservoir for two reasons: 1. You'll likely run into bacteria/slime/fungus issues in the root zone if those temperatures continue (speaking of which, how do the roots look?). 2. Lowering the temperature around the roots will help the plant deal with the higher temperatures above the root zone (outdoors, plant roots usually stay pretty cool, even when it's 100+f in the blazing sun).

Short of that, you'll likely have to start throwing more money at the problem than you'd want.

------------

Sorry I saw the "rubbermaid setup" part and incorrectly assumed you were in DWC.
 

SmeLLyTreeZ

Well-Known Member
We grow weed down here in damn near 100 degree days.... My grow room hits 90 at times. I'm not concerned. lights off it gets in the mid 70's

Seems like a perfect spread of temps...
I agree, of course its not optimal for indoor growing but as long as your watering them when they need it you will be fine! I stressed about this way to much when I first started growing. There are many ways to get you temps down below 90 though..
 

reggaerican

Well-Known Member
good luck getting your temp down im struggling with mine also.. right about 93 right under light but only 85 in room..
 

paOol

Member
im growing this in my closet.
its around 80~ in my room.

the setup is literally 2 x 35 gallon rubbermaids stacked on each other.
the top rubbermaid has 2 exhaust fans. 90 CFM 120mm fan x 2
the bottom rubbermaid has 2 intake fans. 1 x 60 cfm 120mm fan, and 1 80mm 30 cfm fan.

im running 6x 42watt CFL bulbs.

my plants just sprouted 2 days ago, so i haven't put them in yet, they're just chilling in my room.
 

Faldikar

Active Member
If they just sprouted I would recomend not placing them in those heats until they are bigger. An ice bottle or two in front of your fans or hanging inside will help cool things down. Once your girls are bigger and have a set root structure theyll handle the heat a bit better.
 

assasinofyouth420

Well-Known Member
Oh. I get it now. I thought you were in a DWC. Dude thats ingenious. I can see why it would be hard to keep the temps down. I would personally have all of those PC fans on the exhaust. Make sure you get the temps under control before you put them in there otherwise youll stunt their growth. Been there.
 

headshots420

Well-Known Member
If they just sprouted I would recomend not placing them in those heats until they are bigger. An ice bottle or two in front of your fans or hanging inside will help cool things down. Once your girls are bigger and have a set root structure theyll handle the heat a bit better.
This can sometimes do more harm then good. While i have the luxury of a portable a\c unit my roommate does not. He tried the ice method in front of a fan in a small enclosed area such as you described and the temps only went up because the humidity increased. You'll just have to see what works for you though. Good Luck!
 
Top