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Mold during drying / Too fast drying (How should I set up my fan)

Hello. :)

I am a hobby grower from Europe, I've beem growing OUTDOOR guerilla style for 3 years. Every year I've had an issue with drying phase. When I wet trim my plants and leave the whole branches hanging on a string to dry, I've had mold in many spots every single year. I did not have a fan, dehumidifier and not ever humidity and temperature meter. This year when I saw mold again on the first plant that I chopped down I got upset and I bought humidity and tempetarure meter, dehumidifier and two fans. Ever since I installed those two fans, the mold was gone and I haven't had an issue with it ever since.

However I feel like my weed is way too dry. I leave it hanging for 5-7 days, wait until the branches snap and then put my weed into jars. I was surprised that my humidity meter was showing me that in my room there is only aproximately 30% humidity which I understand is way too little and I should be ideally between 50%-60%.

So if you can please answer these questions, I would be really grateful. :)

How is it possible that I get mold on my plants during drying when the humidity inside my room is only 30%?
When I set up my fans, should I point them directly at the branches hanging on the string or should I point them sideways? If I put them directly at the branches, does it have a negatively speed up the drying process which means worse smell and taste? And if I point them sideways, is it possible that there will not be enough air flow in the room and I still get mold? The room is like 5x4metres.

Thank you very much. :)

10 comments

Comments (10)

Living Gardening

Mar 23, 2022

Remember that drying, like curing is supposed to be a controlled release of moisture over time. Two weeks at 60 and 60. If you can hang the whole plant, it would slow the drying. I could see if it dried too fast and the buds had not had time to dry, the moisture left in the buds could cause mold.

The big flag here is that where you are growing and or drying has the mold living there and until you change your conditions or location you will continue to have the problem.

You could try to put something over it that would help to regulate the moisture release like a bag of some type. I cure in paper bags, maybe something similar would work? I have seen ppl washing their buds when green to kill bud rot/mold.

The only other option would be to find a strain that is mold resistant . . .

Good Growing

Cam Z

Mar 25, 2022

Replying to

@Dan Klika no. Powdery mildew is a fungal infection that infects the leaf tissue of a plant when it is weak enough to parysitise. Powdery mildew looks like a white/gray powder on the surface of a leaf. The issue that you are having is with a fungus called botrytis. Botrytis only becomes an issue during the late flowering stage when the space between nodes swell and lose the ability to evaporate water away from the buds properly. Powdery mildew can affect a plant at pretty much any stage of growth if conditions are optimal. While they are not the same, the conditions that all fungi favor are generally the same. Fungi require high relative humidity and low air exchange to develop. Preventing one will always help in preventing the other. If you have the ability next season try and remove any fan leaves that face towards the inside of the plant canopy about 3 weeks before harvest. The increased airflow will help reduce your chances of developing a fungal infection. Another thing you may want to consider is to keep in mind when it is going to rain while in your harvest window. I would harvest early rather than expose the plants to rain in late stage flower. The reason your style of growing is more likely to cause this problem ultimately stems from a lack of good airflow (thats one reason why farmers grow in cleared fields). Also, the more direct light your plants get the better. Uv radiation inhibits the growth of fungus. Hope that helped.

Cam Z

Mar 25, 2022

Replying to

People call powdery mildew pm and they call botrytis bud rot.

Dan Klika

Mar 25, 2022

Replying to

@Cam Z WoW thanks so much man! I really appreciate it.

Cam Z

Mar 23, 2022

Sorry about your luck with mold. The main reason you are getting mold is because of the way you grow. Since your plants are essentially growing in the forest they are exposed to billions of fungal spores. Those spores are just waiting for the right conditions to germinate. Even if you dry the bud you are smoking those spores. I would highly suggest bud washing if this has been a consistent issue for you. Might be too late if you have already started drying for a bit but if not look up some videos on it.

To answer your questions, the rh of the room is okay but if you weren't using a fan to circulate air in the room then there were likely stagnant pockets of air in the immediate vicinity of your plants with a much higher humidity. You should not blow fans directly on the plants. The best place you could put your fan in a room that large is directly under your plants blowing the air away from them. Chances are that the mold has already inoculated on your buds though and by cutting the plants down you initiate the last phase of the cycle by making the plants weak enough to colonize.

Again, if you are having an issue with mold I highly reccomend bud washing. You can mix up a solution with lemon juice, cold tap water and some peroxide. You just jiggle the branches in the water for about 15-30 seconds. You can place a fan directly on them for a few hours after that to remove the extra moisture then go back to the above mentioned technique. Check your buds for any signs of mold before hanging to dry and remove anything that looks suspicious. Mold spreads very quickly and you have to remove anything within a few cm of what you see.

Hope this helps!