How do I lower the humidity in the greenhouse

[EugeneTheGrower]

Hello, we have near 1000 plants growing in greenhouse. We are located in Poland and the autum is coming...

Last year guys who were renting this greenhouse before us encountered the mold issue on the end of the harvest. They've lost 30% of the crop. I notice that we have water on the foil ground whereas few weeks ago it was remaining dry. I will decrease the amount of watering but I think I need more action.

We have 3 fans on the top and I think that is not enough and they move air only at the top layer of the greenhouse. How do I dry the ground which is covered by dense foliage?

As I was writing this post I've came with idea to defoliate plants. But still I would be glad to listen to your ideas. Thank you

 

[Homesteader]

Maybe you could add clean dry sand to the ground to absorb some of that moisture? Is there any way to open or roll the sides up to get a cross flow underneath?

 

[m8ty]

what about Adding an Air Conditioner?

 

[MIGrampaUSA]

what about Adding an Air Conditioner?

Most greenhouses are not sealed tight enough to allow for efficient air conditioning. It would be like trying to cool the whole county. I have a large hoop house and I've dealt with the bud rot before. It's a pain to try to control that humidity, and it gets much worse in the fall.

I would use early maturing strains and keep them short enough and spaced out so they aren't up against the wet greenhouse walls. All the air flow/cooling in the world will not stop bud rot, mold, or wpm if your flowers are up against a wet surface.

 

[GNick55]

a messy grow area tells me your new and a 1000 plants? now you invested so much money and time?
your going to get mold more from it being dirty than the moisture, but the combination is even worse, geez clean up that mess. you need enough fans so those plants are blowing around.. fresh air coming in?

 

[1diesel1]

a messy grow area tells me your new and a 1000 plants? now you invested so much money and time?
your going to get mold more from it being dirty than the moisture, but the combination is even worse, geez clean up that mess. you need enough fans so those plants are blowing around.. fresh air coming in?

Ditto, if you can get some commercial fans on one end and open the other it will save your ass. I’m talking some serious air flow, no little bathroom fans like what you’ve got.

 

[MIGrampaUSA]

I'm using two 1650 cfm attic fans. I have one like in @1diesel1's example as an exhaust and one similar to this here: https://www.homedepot.com/p/Master-...-Gable-Mount-Gable-Louver-Vent-EGV6/205924917 as an intake fan

They work well for me until the fall when my area of the country has cool damp nights and many rainy/overcast days. Once night time temps are consistently in the 40's, even running the fans 24/7 does not remove condensation from the greenhouse glass.

 

[EugeneTheGrower]

what about Adding an Air Conditioner?

It should be a really powerful one. We will not stay here for long

 

[EugeneTheGrower]

Maybe you could add clean dry sand to the ground to absorb some of that moisture? Is there any way to open or roll the sides up to get a cross flow underneath?

What do you mean by "open or roll the sides up"?

 

[EugeneTheGrower]

Most greenhouses are not sealed tight enough to allow for efficient air conditioning. It would be like trying to cool the whole county. I have a large hoop house and I've dealt with the bud rot before. It's a pain to try to control that humidity, and it gets much worse in the fall.

I would use early maturing strains and keep them short enough and spaced out so they aren't up against the wet greenhouse walls. All the air flow/cooling in the world will not stop bud rot, mold, or wpm if your flowers are up against a wet surface.

Do you mean that flowers that are touching the walls are destined to mold?

 

[EugeneTheGrower]

a messy grow area tells me your new and a 1000 plants? now you invested so much money and time?
your going to get mold more from it being dirty than the moisture, but the combination is even worse, geez clean up that mess. you need enough fans so those plants are blowing around.. fresh air coming in?

Yes, there are windows on thr ceiling we can open. You are right I would clean everything starting from monday

 

[MIGrampaUSA]

Do you mean that flowers that are touching the walls are destined to mold?

Yes, if the glass is wet. If you have condensation on the walls and your flowers are touching those walls, it's almost certain to cause mold/rot issues.

 

[Homesteader]

Just stole this image off of google but you create a complex airflow when using the sides as well as the dormer vents. Obviously not something you are going to build on the fly for this season but hope you figure it out nonetheless

 

[Nate_in_AK]

I don't see any motion of the leaves in your video. Airflow seems to be a staple in the foundation of good cannabis in everything I've read. I gotta believe you would benefit from about 100 more fans (or you know 10 really big good ones?) Especially if your humidity is high. I'm sure I've read multiple places that high humidity can be managed with adequate airflow. Keep us posted on how it goes!!

 

[Ponky]

Greenhouse fans. Indoor fans. Reduce the amount of plants if needed. Call the local greenhouse guys. Buy some fans.

 

[EugeneTheGrower]

Unfortunately, there are mold issues. Mold had infected only plants that are on the final flowering stage(132 plants of 1656 plants). I moved those to another greenhouse. Mold continues developing but in a slower pace. There is 1 week till harvest, I think it is too late to use anti mold agents