Jump to content
  • Sign Up

best hours for flowering at night to escape heat. Weather GURUS!

Recommended Posts

Hey guys. What do you think is the best hours to flower during the night? I currently have set it from 8pm till 8am.... but im thinking 9 till 9.

Any weather experts here?


My single 600w bulb. That mind you is exhausted by a 8inch blower into the roof. And a 6inch fan from the window cannot cool down a bedroom. Its 30C room tempature. Youd think having an open room it would be fine. Very wrong. I think i need a fan controller to adjust the tempature so they can cut in and out and work.it out for themselves. I have the hot air circulating within my roof. I think I might have to start hacking off the roof tiles to get it OUT of the roof. Or run a longer duct right away from the room. The duct goes up just above the roof the setup is in.



My adjustawing i LOVE but they are just too damn hot. 30C room temps in an open room with intake and exhaust (nice phresh fans mind you) is kind of ridiculous. Im thinking of upgrading my exhausf to a 10inch exhaust which is 1100CFM i currently have a 720cfm at full tilt. And HYPERFANs mind you...

I want 2000 watts eventually in the room.


Any ideas guys whats going wrong here?

Link to comment
Share on other sites

I run 8:30 to 8:30 but that's more to do with when i'm home than best time to do it 


get the light in a tube or hood , you won't loose as much light at the ends as you do with a ajustawing 

all poss light focused downward


you could also close loop the light , ducting sucking from outdoors then attached to the tube or hood & more ducting blowing in the roof 

no air from the light indoors 


if you have bends in ducting , can you remove them for straight runs of duct , more efficient 


Fans , sucking is more efficient than blowing but the fan is running hot , shorter life span , blowing is not as efficient but runs cooler = lasts longer 

short runs = blow , long runs = suck 

Link to comment
Share on other sites

6:30-7:30 AM  the coldest hr of the day

very noticeable in summer.


I used to run 8pm till 8am or 9pm till 9am


Only because the day would heat up again by 10am.

day usually cooled down by 10pm.


One year I ran 24/7 intake from outside in 40c+ heat.

plants looked a little smashed from heat.

9pm to 9am still got 250g+ from a 400watter hps.

that room was hotter during the day too.

so if you can stomach looking at withered leaves after week 6 or so of flower you'll be fine to harvest :D

i went the whole 70days.

last week of november till last day of jan.

i used aircooled hood and fan was sucking air from it out a filter into the room.

6" inline was pumping air from outside directly into the tent inlet.

cannabis can withstand a bit of heat if you let em sit there and continue

harvest was legit smoke after a cure.


Just water your plants more often with cool water as the heat dries em out quicker.

Lots of aeration to the nutrient feed was key to nice yield

Link to comment
Share on other sites

I run my lights through the day, even through summer. It is a battle, but can be done. Imo it is most important to keep the roots cool, rather than air temp. Use bottles full of frozen water in the res if running recirc.


I am currently in coco run to waste, and just put in cooltube for the first summer and the soil (coco) temp sits around 26C. Leaf temp fluctuate more but sit around 28 - 32 Plants are healthy.

Link to comment
Share on other sites

unless you have aircon, in the height of summer there's fuck all you can do no matter how efficient your setup is.... what are you going to do on 40c days(which we will def get)? buy an air-con, run DWC with fucking expensive ass chiller and pump the silica, that's about it... its really the root temps that play a major part indoors, outside they are surrounded by inches of soil insulate them from the heat.


point your intake duct inside ur tent, at your roots/pots.... might help

Edited by Xanode
Link to comment
Share on other sites

Bringing 35c heat through the intake in the window is just shithouse.


I need to return to my property. 3hrs from sydney . Head south and west a little. 8c in the nighttime. Mateys still pumping 2k watts in a 2.2m by 1.5m long old cupboard. Averaging about 111watts per square foot.


Hydro in summer is location location location. Hydro shops are real quiet atm. Alot of guys just yeah. Stop growing for 2 months. To get out of that severe punch of summer

Link to comment
Share on other sites

have you considered a closed loop , once the light loop is closed , that 35c air isn't entering the tent & needs no filter ,

it's only running across the light in a tube & out , should help a little to keep tent temps down ,

but 35c air across a hot hid in a tube is not ideal 


can you install one of those whirly gigs on the roof to suck roof air out , "i think" you can buy a powered or wind driven unit

could prob attach a exhaust fan & duct straight under it & stop it from spinning or let it spin & on windy days no exhaust fan needed 


Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

By using the community in any way you agree to our Terms of Use and We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.