Temp and humidity in flower

[SHRED]

What temps and humidity are you running in your grow space during mid to late flower?

I'm maintaining mid to low 70F's with a 40%-50% rh range.

To accomplish this I somehow fit my dehumidifier in there. It wasn't easy but has really helped bring down the rh which was running too high.

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[St. Tom]

What temps and humidity are you running in your grow space during mid to late flower?

I'm maintaining mid to low 70F's with a 40%-50% rh range.

To accomplish this I somehow fit my dehumidifier in there. It wasn't easy but has really helped bring down the rh which was running too high.

.
View attachment 1549733View attachment 1549734

I've always founds as I've got a strong extraction fan if my humidity is popping up highering that seems to take it down a little but at your age in flower as long as I'm under 50rh I'm happy and good air circulation helps and I keep my temps late 70s to 80 f

 

[BII]

I prefer temp. in upper 70s. And in winter, my tent generally runs at 20-35% humidity with no correction, with no visible related problems.

What increases your rH so much that it's a problem (Is it summer where you are)?

 

[SHRED]

I prefer temp. in upper 70s. And in winter, my tent generally runs at 20-35% humidity with no correction, with no visible related problems.

What increases your rH so much that it's a problem (Is it summer where you are)?

Summer is bad.

But Winter even though better still needs a dehumidifier in there I've found out.

 

[TrichomeAssassin]

Almost ready to harvest. I am at 79 degrees with canopy humidity at 31%.

 

[American Hillbilly]

When my plants reach the "stretch" phase is usually when my humidity problems start. With a LED light I don't make enough heat to worry about extracting heat. It's all a big balancing act, because in the winter I have to humidify half way through, heat the entire time, and then dehumidify in the second half. If I ran my fan at the speed needed to extract humidity, I'd be sucking all my heat out.

I try to not drop much below 50% RH until later into flower (about where you are at now it looks) when the buds start stacking. Anything under 50% is good for me through the depths of flower and I do not get PM. Depending on the season, I try and drop my temps to bring colors out in late flower. In the winter that's easy; in the summer not so much. Do you have a IR thermometer? I like to watch leaf temp and worry about it more than ambient air temp. Ambient temps for me are mid to upper 70s in late flower.

I use the same dehumidifier btw!

 

[SHRED]

When my plants reach the "stretch" phase is usually when my humidity problems start. With a LED light I don't make enough heat to worry about extracting heat. It's all a big balancing act, because in the winter I have to humidify half way through, heat the entire time, and then dehumidify in the second half. If I ran my fan at the speed needed to extract humidity, I'd be sucking all my heat out.

I try to not drop much below 50% RH until later into flower (about where you are at now it looks) when the buds start stacking. Anything under 50% is good for me through the depths of flower and I do not get PM. Depending on the season, I try and drop my temps to bring colors out in late flower. In the winter that's easy; in the summer not so much. Do you have a IR thermometer? I like to watch leaf temp and worry about it more than ambient air temp. Ambient temps for me are mid to upper 70s in late flower.

I use the same dehumidifier btw!

I do have one.
What leaf temps do you like to get?
Of course the upper plant is the higher temps.

 

[American Hillbilly]

I do have one.
What leaf temps do you like to get?
Of course the upper plant is the higher temps.

From what I understand low 80's is ideal on fan leaves for optimal growth, and using that knowledge I have not seen any issues in my tent. I will try to get that temp on the highest fan leaves and adjust my ambient air temp accordingly. My goal is 81-82 degrees and my plants seem to be happy with that. I like to experiment, and with auto's that can be tough to see process changes v strain differences, but I have been very pleased with my results so far. Lots of factors affect leaf temp, so I find it much more interesting to watch that than ambient air.

The most shocking revelation I had with the IR thermometer, was how high I have to run my ambient temps to get leaf temp where I want it. LEDS will do that.

 

[SHRED]

From what I understand low 80's is ideal on fan leaves for optimal growth, and using that knowledge I have not seen any issues in my tent. I will try to get that temp on the highest fan leaves and adjust my ambient air temp accordingly. My goal is 81-82 degrees and my plants seem to be happy with that. I like to experiment, and with auto's that can be tough to see process changes v strain differences, but I have been very pleased with my results so far. Lots of factors affect leaf temp, so I find it much more interesting to watch that than ambient air.

The most shocking revelation I had with the IR thermometer, was how high I have to run my ambient temps to get leaf temp where I want it. LEDS will do that.

Captain Redbeard (my seed source) says he likes to keep his leaf temps about 72F. We were discussing while in flower though.

 

[American Hillbilly]

Captain Redbeard (my seed source) says he likes to keep his leaf temps about 72F. We were discussing while in flower though.

72 seems very cold to me, but I'm just an amateur. I have great results at low 80s lst. I wonder why he recommends so low? If one was using HPS bulbs, your room would have to be super cold to get those kid of LST.