Hello, I’m posting because I have a 1x1x2 tent, I’m in the first week of flowering and the temperature when the LED is on is 20 C and 60 to 65% humidity, so far so good. When the LED turns off at 10:00 in the morning, the temperature drops to 18 C but humidity stays around 65%, but when the sun goes down at 18:00 the temperature stays the same but humidity spikes up to 75%. That four-hour increase worries me; since it’s my first time, I don’t think I’ll be safe from fungi, seeing as even experienced users harvest early to avoid mold.

So obviously this is solved by buying a €150 dehumidifier, all in good time, but does anyone know homemade tricks to lower humidity?? Or should I just assume that once I get decent buds mold will ruin all my hard work? Around this time of year it’s normal for it to rain and that also drives humidity up. I used to be a long-haul truck driver all over Europe, traveled through the Black Forest, and I know humidity is high there—how do you guys do it??
Tricks, advice?? I turned the extractor fan up to speed two and all I managed to do was lower the temperature.

When you water, water in the morning 2 hrs after lights been on, lots of fans. It’s almost impossible but I don’t use anything for humidity/ dehumidifier an last grow I had 13 of em flowering

But ya a couple fans oslating on low on plants is about the only way

My grow room tends to run in the 60s RH and I just add good air circulation with a fan or 2 and end up okay each grow so dont stress it to much and spend money when not necessarily needed. A good humidifier/dehumidifier is ideal to help give your plants the best environment possible but not a deal breaker. A nice small oscillating fan and leaving a breathing hole port open on your tent will help ya out a lot and get ya through flowering stage.

Its when the moisture stays stagnant and settles on the flower is when bud rot or mildew appear in most cases but all in all your numbers aren’t very bad and continue asking any questions or concerns you have. We are all happy to help out

No man no, 150 euros for a dehumidifier, buy a 30 or 40 euro one on Amazon, we’re crazy xD
For high humidity, sativa plants work better. If you look at it, the structure of sativas is anti-humidity: thin leaves, separated buds. For tropical / humid regions, sativas are a much better option than indicas with broad leaves and fat, compact buds.
I would tell you, in my limited experience with fungus, that the problem is always aeration. If there is enough air renewal, including the air blowing on the plants, it’s very hard for mold to grow. If it appears, it would grow inside the buds, which is right where the air doesn’t reach, but lots of air definitely helps because the microclimate the fungus needs to proliferate isn’t generated if air blows continuously.
Then you have things like only watering before turning the lights on, never when turning them off.
Strong or maxed-out extractor fan, and good hygiene in the grow tent

Ciao Polentona1971, my extractor fan works great for this situation.

If you run the lights from 6pm until 6am or whenever is most humid you could dodge the most naturally humid hours and have solid air flow going the whole time it would reduce risk a lot.