Humidity issues at night! Afraid it might ruin my buds.... HELP!!

AlChemist333

Active Member
When the lights are on in my grow tent, temperature is usually between 74-76 degree F and humidity is usually around 49-52%. At night I noticed it increases drastically to about 60-64%. Im on my last few weeks of flower. My buds hasn’t fattened much, Smells like grass or hay. However they are sticky. I have two mini dehumidifier insides the tent. Oscillating fan for the top of my canopy, and one at the bottom to eliminated stagnant air on the floor of the tent. I have an intake fan and exhaust fan with carbon filter i run consistently. Not sure what to do at this point. I only notice the humidity drops when my lights are on. Can anyone provide any advice on this issue? I’ve waited forever to get to this point and I don’t want to ruin them by possibly causing bud rot.
 

Keesje

Well-Known Member
What is the temperature at lights out?
You already have low temperatures during lights on.

What kind of lights do you have?
 

Bukvičák

Well-Known Member
60-64 is not such terrible if you said that your buds are not so fat (in the botrytis and WPM sight). Problem is that high humidity in late flower means less trichromes production. Run the lights on at night and off during the day with ventilation on same level as with lights on.
 

its.always.420

Well-Known Member
Might need another extraction fan to suck more wet air out during lights off, and if you can raise the temp around your grow it will help too. You can always add a heater with a timer set come on during the dark cycle
 

Keesje

Well-Known Member
The whole question is more complex.
Humidity in itself does not say everything.
It is humidity, related to ambient temperature, related to leaf temperature.

Also to prevent root rot it is important to prevent dew on your buds.
My english is not good enough to explain it. Sorry.
 

AlChemist333

Active Member
60-64 is not such terrible if you said that your buds are not so fat (in the botrytis and WPM sight). Problem is that high humidity in late flower means less trichromes production. Run the lights on at night and off during the day with ventilation on same level as with lights on.
Will it be okay to let the plants sit in the dark for an extra 12 hours during late flowering to make that transition?
 

AlChemist333

Active Member
60-64 is not such terrible if you said that your buds are not so fat (in the botrytis and WPM sight). Problem is that high humidity in late flower means less trichromes production. Run the lights on at night and off during the day with ventilation on same level as with lights on.
I’m in Week 9 of flowering and don’t want to fuck anything up.
 

AlChemist333

Active Member
The whole question is more complex.
Humidity in itself does not say everything.
It is humidity, related to ambient temperature, related to leaf temperature.

Also to prevent root rot it is important to prevent dew on your buds.
My english is not good enough to explain it. Sorry.
Even the humidity gets a little high ive never noticed any dew formation on the leaves. However, I’m thinking maybe the environment outside of my tent humidity is higher than that inside so the intake fan is constantly pulling in air with high humidity and it’s working my two mini dehumidifiers I have inside the tent. I’ve defoliate a few weeks ago and I’m on Week 9 of flower.
 

AlChemist333

Active Member
Even the humidity gets a little high ive never noticed any dew formation on the leaves. However, I’m thinking maybe the environment outside of my tent humidity is higher than that inside so the intake fan is constantly pulling in air with high humidity and it’s working my two mini dehumidifiers I have inside the tent. I’ve defoliate a few weeks ago and I’m on Week 9 of flower.
against*
 

Jimdamick

Well-Known Member
Humidity levels at 65% are acceptable, if they run into the 80's then you might have an issue with bud rot.
Keep your lighting schedule the same, (I run 11 on/13 off)
Good luck :)
 

Bukvičák

Well-Known Member
Put them
Even the humidity gets a little high ive never noticed any dew formation on the leaves. However, I’m thinking maybe the environment outside of my tent humidity is higher than that inside so the intake fan is constantly pulling in air with high humidity and it’s working my two mini dehumidifiers I have inside the tent. I’ve defoliate a few weeks ago and I’m on Week 9 of flower.
put them outside the tent aprox half meter from your intake hole
 

Star Dog

Well-Known Member
If the humidity outside is 75/80% as it often is for me you need to crank up the heat to reduce the rh%.
It doesn't matter how much air you pull through your bringing in 75/80% air without heating it sufficiently you'll never get it down without more heat.

Keeping the environment right through the season is a constant battle, you need to put up with it or throw money at it I'm afraid.

I've done a number of crops with night high rh and low temps with minimal hassle, as long as air is passing through you'll be fine.

What's your outside temps and humidity?
 

AlChemist333

Active Member
If the humidity outside is 75/80% as it often is for me you need to crank up the heat to reduce the rh%.
It doesn't matter how much air you pull through your bringing in 75/80% air without heating it sufficiently you'll never get it down without more heat.

Keeping the environment right through the season is a constant battle, you need to put up with it or throw money at it I'm afraid.

I've done a number of crops with night high rh and low temps with minimal hassle, as long as air is passing through you'll be fine.

What's your outside temps and humidity?
Humidity outside my grow tent is usually around 62-63% and temp I keep around 70 degrees, Im going to try place my mini dehumidifiers outside my tent near the intake fan and see if that helps first. If not I’ll buy a bigger dehumidifier for the outside of my tent since I’m using one of my rooms.
 
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