Different Drying parameters - question

TCH

TCH

Well-Known Member
I understand that the ideal drying setup would be 60°F and 60%rh.

I also understand that in the real world, sometimes it isn't possible or feasible to maintain that.

My question is as follows. If the temperature is able to be maintained between 65 and 71°F what adjustment should be made on the RH? Like, does VPD come into play for drying like it does for growing where there isn't just a set humidity, but it also depends on the temperature?

My recent dry only took 5 days and it was actually a little too dry. The buds when jarred leveled out at 51-52% rh. I ran a humidifier outside the tent hooked to an Inkbird controller and it worked exactly as it should have. At ~57%, the humidifier kicked on until 60%. But, my temps were a little high as I kept them between 65 and 71°F. The rh fluctuated between 56 and about 61%.

I'm well aware that the fact my buds were really airy and not very dense definitely played a part in the quick drying, but I still feel like it should have taken a little longer.

My setup is a 2x2 tent
4"inline fan and filter pulls air from bottom of tent and exhausts out the top.
6" pole fan that is pointed towards bottom of tent to keep air circulating but not blowing on the hanging buds.
Inkbird controller set at 57 and 60% hooked to cool mist humidifier outside of the tent.

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D

Dark_Hatchling

Well-Known Member
TCH said:
Is this a stupid question? Am I overthinking this?
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Nope. I'm watching this thread to see if anyone has input regarding drying.

I've struggled with drying myself. This year I have nearly the same exact setup as you, just a larger homemade "tent" and my humidifier is inside the tent. I have my Inkbird setup at 60%RH with the dehumidification setting at 61% and the humidification setting at 59%, it definitely maintains 60%RH nearly perfect all throughout the day. Temps in the house have been under 76F, no lower than 69F or so, though.

I harvested 10/15 and 10/16. As of today, the buds seem too wet for jars. Smell seems a bit off on the outside of the buds. But yeah, just waiting to see how it turns out in the end.
 
Fallguy111

Fallguy111

Well-Known Member
Airy buds dry fast. Since you're in a tent I'd thin you could have vented less, maybe every hour at first and then a few time a day towards the end. Theoretically you shave able to cure in a tent if you can maintain temp/rh by exhausting instead of burping.
 
Star Dog

Star Dog

Well-Known Member
My last crop I used a dehumidifier, the temps were 18-20c circa 85/90% rh.
I set the dehumidifier to 62-70% on a cycle timer, when the humidity got down a bit i used the cycle timer and the dehumidifier controller to keep it between 60-62%.
When I put it in buckets 14/16 days later the humidity settled at 62%.

My logic was if I control the rate of humidity then by default i control the drying period regardless of the temps?
 
TCH

TCH

Well-Known Member
Fallguy111 said:
Airy buds dry fast. Since you're in a tent I'd thin you could have vented less, maybe every hour at first and then a few time a day towards the end. Theoretically you shave able to cure in a tent if you can maintain temp/rh by exhausting instead of burping.
Click to expand...
I just dried in my tent. I then moved it to a jar and some grove bags for cure/storage.
 
H

Hydro Hippie

Member
TCH said:
I understand that the ideal drying setup would be 60°F and 60%rh.

I also understand that in the real world, sometimes it isn't possible or feasible to maintain that.

My question is as follows. If the temperature is able to be maintained between 65 and 71°F what adjustment should be made on the RH? Like, does VPD come into play for drying like it does for growing where there isn't just a set humidity, but it also depends on the temperature?

My recent dry only took 5 days and it was actually a little too dry. The buds when jarred leveled out at 51-52% rh. I ran a humidifier outside the tent hooked to an Inkbird controller and it worked exactly as it should have. At ~57%, the humidifier kicked on until 60%. But, my temps were a little high as I kept them between 65 and 71°F. The rh fluctuated between 56 and about 61%.

I'm well aware that the fact my buds were really airy and not very dense definitely played a part in the quick drying, but I still feel like it should have taken a little longer.

My setup is a 2x2 tent
4"inline fan and filter pulls air from bottom of tent and exhausts out the top.
6" pole fan that is pointed towards bottom of tent to keep air circulating but not blowing on the hanging buds.
Inkbird controller set at 57 and 60% hooked to cool mist humidifier outside of the tent.

View attachment 5215260
TCH said:
Is this a stupid question? Am I overthinking this?
Click to expand...
You are definitely not over thinking things. The drying process is equally as important as the growing process. Temperature is important and will influence the speed of dry-down.

As you mentioned it is not always possible to get a perfect 60/60 temp/humidity. My suggestion to you is work with what you have to dry things as slow as possible. I shooting for a 14-16 day dry. In order to accomplish this I have had to adjust my humidity to 70%. The big watch out for a high humidity dry-down is always mold. To mitigate that threat I increase air flow.

If you are going to increase temperature from 60 to around 70 that will facilitate a faster dry. So you will need to raise your humidity to prevent a premature drying.

Have you ever smokes weed that smells and tastes like hay? Many times that is the result of a dry-down that went too fast...maybe 5 days or less.

You have a very similar setup as I do. I put my 3x3 dry tent in a small 10x10 room. That way I can put my dehumidifier, humidifier and fan with carbon scrubber outside the tent but in the same room. I could not get the long slow dry without all three pieces of equipment working together.

With buds that aren't very dense there is less risk of mold. I think you did everything right but instead of keeping your humidity near 60 you should have used 70 as a set point. Keep in mind that with dense buds 70 humidity could get you into trouble.
Click to expand...
 
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TCH

TCH

Well-Known Member
This is exactly what I was thinking in my head, but wasn't sure if it was a silly and hopeful thought or would actually work. I'm really looking forward to the next plant to come down now. Thank you
 
H

Hydro Hippie

Member
Dark_Hatchling said:
Shit, you can get away with cranking the humidity up to 70%?
Click to expand...
Absolutely. I do it all the time. I would not suggest doing 70% humidity on day one or two of drying. I am also pulling 900 cfm though my 3x3 drying tent when at 70% humidity. As the humidity goes down I turn the airflow down as well.

I would much rater dry and cure at 60% humidity but if things are progressing too quickly I would rather increase the humidity so my flowers doesn't dry too fast and smell like hay. I should also mention that I really only have to raise the humidity to 70% on my indoor harvest because I wet trim.

On my outdoor I hang the entire plant fan leaves and all. When done this way the fan leaves curl around the buds and help retain moisture. This slows down the drying process. If I tried to run 70% in that situation I would have problems for sure.
 
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pahpah-cee

Well-Known Member
I believe with drying we look at RH, temp, and Dew point.

You want to pull the moisture from the material as slow as possible. People suggest under 65F for terpene preservation.
 
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