Humidity and White Widow Autoflowers

This is my 5th grow of white widow autoflowers. I have 4 plants at the beginning of flowering stage. Temps during day cycle 75-79 degrees. Dark cycle 71-73 degrees. RH 50-60% day and dark cycle. Running 2 240 CFM input and exhaust fans plus 2 6 inch oscillating fans inside tent. Plenty of air circulation. Installed 2 mini dehumidifiers to lower the humidity. Still 50-60%. Temps and humidity have been high these past few weeks. With all my air flow during flowering will my plants possibly avoid getting moldy?

I would think about trying to get the humidity down lower.
With all the air exchange your dehumidifiers are probably ineffective.
Try less air exchange and see if you can get it below 50%
High 70s with 60% humidity is a bit concerning.

Plants Humidity Level
Growth Week 1 60%
Growth Week 2 60%
Flowering Week 1 55%
Flowering Week 2 50%
Flowering Week 3 50%
Flowering Week 4 50%
Flowering Week 5 50%
Flowering Week 6 45%
Flowering Week 7 45%
Flowering Week 8 40%
Flowering Week 9 40%

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Hi Spiney
Thanks for your reply. I typically do my grows in Late August or early September when humidity is lower. This is my first mid summer indoor grow. I have variable controls on my input and exhaust fans. Do think slightly reducing exhaust or input flow would possibly remedy my humidity problem?

Try it and see
It should change within an hour or so.


The reduction of air flow did not do the trick. I did some reading and they say increase air flow in your tent. This way humidity evaporates off your plant quicker. I added another fan inside my tent and opened up some lower vents on the bottom of the tent to allow more air flow through the bottom. I was able to drop my RH by 5 %. Another factor I could try is adding a small space heater to raise the temps inside the tent to reduce the humidity. This would mimic the dry conditions I have when I grow closer to the fall late August/September. Any thought on that?.
Thanks for all of your help