Growing in low humidity

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Lisa22

Lisa22

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I am running 2 4x4 tents with 4 600 leds in each tent. 5 gal buckets organic soil. The humidity here has been 20%. The plants are 4 week veg. I have small humidifiers in each tent but the humidity is staying at 40%. I have a swamp cooler that I run in the summer that brings that humidity up but if I run it now it keeps my temps at 69/70 degrees.
What happens if you grow a crop with that low of humidity? Or with better humidity and lower temps? Should I buy 2 more small humidifiers? Run the large swamp cooler? Appreciate any thoughts.
 
B

Burned Haze

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Get it to a higher humidity !

Veg stage :
60-75% humidity and you can have 80-86f easy canopy Inless seedlings
Flower: 55-65% humidity (keeping it at 65-60% in beginning of flower to 3/4 stage of flower, than lower to 55%-60%)


Suggestion for knowing your room when your not there, check out Pulse environment control ( all you need is internet access to the pulse and that’s it, the thing will tell you everything you want for your environment and you could be anywhere in the world and you can set daytime/nighttime differences and it will alert you if anything is out of whack by emailing you . Super easy and I think it’s going to beat a lot of those expensive controllers I wanted to buy before)

I know it only takes a few days or even one of off temps or humity to make your buds look like foxtail bs or major yield loss and all you need is a controller and make sure to not allow such things to happen ( makes me sound ocd but more years I grow it makes me this way lol )

anther thing if you need more humidity in the room, just add some buckets/Rez of water and set your dehumidifier down obviously .
 
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JWM2

JWM2

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With a high VPD your plants will use more water. A side effect is your plant will absorb more nutrients than it needs if they are present in the growing medium. If this happens your plants will show nute burn. Your growing medium will also dry out too quickly. The plants will grow lanky and sparsely and yield will suffer accordingly.

The right VPD can make all the difference in the world. Too low and your plants won’t get enough nutrition, too high and they’ll get too much.
 
Lisa22

Lisa22

134
43
Get it to a higher humidity !

Veg stage :
60-75% humidity and you can have 80-86f easy canopy Inless seedlings
Flower: 55-65% humidity (keeping it at 65-60% in beginning of flower to 3/4 stage of flower, than lower to 55%-60%)


Suggestion for knowing your room when your not there, check out Pulse environment control ( all you need is internet access to the pulse and that’s it, the thing will tell you everything you want for your environment and you could be anywhere in the world and you can set daytime/nighttime differences and it will alert you if anything is out of whack by emailing you . Super easy and I think it’s going to beat a lot of those expensive controllers I wanted to buy before)

I know it only takes a few days or even one of off temps or humity to make your buds look like foxtail bs or major yield loss and all you need is a controller and make sure to not allow such things to happen ( makes me sound ocd but more years I grow it makes me this way lol )

anther thing if you need more humidity in the room, just add some buckets/Rez of water and set your dehumidifier down obviously .


Thanks for the kick in the rear. I was hoping but know better and know what the humidity should be. I'm buying 2nd humidifiers for the tents today. I don't have a dehumidifier - it's call Nevada. I have a humidifier and pans of water in there too and still the humidity is at 38%. The One Pulse looks amazing but the cost seems high to me right now. Glad to learn about it wish there was something that cost less as I have 2 small tents. Again thank you so much for taking the time to write this!
 
Lisa22

Lisa22

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With a high VPD your plants will use more water. A side effect is your plant will absorb more nutrients than it needs if they are present in the growing medium. If this happens your plants will show nute burn. Your growing medium will also dry out too quickly. The plants will grow lanky and sparsely and yield will suffer accordingly.

The right VPD can make all the difference in the world. Too low and your plants won’t get enough nutrition, too high and they’ll get too much.
Thank you - I'm getting another humidifier today and hope that they won't hemi on me in 4 months. I will live with reduced yield and be happy getting anything on this one. I appreciate the explanation and the quality of information you all provide us. This has been my community for help and it is greatly appreciated.
 
Brianhauser

Brianhauser

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I am new to growing and I’m using a deep fryer for heat . Just leaving the pilot light on is enough. I first filled it with water and humidity was around 60%. I then drained it and the levels dropped to 35-40. My plants seem to have stopped growing although they look healthy.? I don’t get a lot of fresh air but run an exhaust fan several times a day and a window is cracked open. Any suggestions
 
Beachwalker

Beachwalker

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I am new to growing and I’m using a deep fryer for heat . Just leaving the pilot light on is enough. I first filled it with water and humidity was around 60%. I then drained it and the levels dropped to 35-40. My plants seem to have stopped growing although they look healthy.? I don’t get a lot of fresh air but run an exhaust fan several times a day and a window is cracked open. Any suggestions
 
goingtoguano

goingtoguano

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I grow in a low Rh environment (30-45%) during the winter and I just don't consider it to be that big a deal (no lanky plants or poor yields). I mean, yeah I end up with some crispy dry leaves ect and I have to water often but the low Rh doesnt seem to have such a large negative impact that I would want to try to artificially introduce more humidity via humidifiers. Humidifiers can bring some negatives of there own with things like mineral deposits (unless you run RO or distilled water) and molds. I haven't used them for a grow but I have seen some really gross humidifiers that I wouldn't want anywhere near my living space, never mind my growing area. To each there own. I'm not criticizing anyone for trying to get their environment into more ideal conditions but like everything else, there are potential negative issues that don't get much discussion.
Disclaimer: my temps are low as well. Every time I see the VPD chart, all I can think is how I would be really concerned with getting PM if I was in that sweet spot.
 
Lisa22

Lisa22

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43
I grow in a low Rh environment (30-45%) during the winter and I just don't consider it to be that big a deal (no lanky plants or poor yields). I mean, yeah I end up with some crispy dry leaves ect and I have to water often but the low Rh doesnt seem to have such a large negative impact that I would want to try to artificially introduce more humidity via humidifiers. Humidifiers can bring some negatives of there own with things like mineral deposits (unless you run RO or distilled water) and molds. I haven't used them for a grow but I have seen some really gross humidifiers that I wouldn't want anywhere near my living space, never mind my growing area. To each there own. I'm not criticizing anyone for trying to get their environment into more ideal conditions but like everything else, there are potential negative issues that don't get much discussion.
Disclaimer: my temps are low as well. Every time I see the VPD chart, all I can think is how I would be really concerned with getting PM if I was in that sweet spot.
Thanks so much for letting us know about your grow in low humidity. I'm happy to hear that the low Rh hasn't affected your plants as it means that mine will probably be fine too. The humidity was down in the 30s for over a week with my grow. I put a second humidifier in there last week and they already seem like they have grown more - with the low humidity they seemed to be just sitting there. You are right about humidifiers - they have to be taken care of! There is a product that you put in every time that keeps them clean w/o mineral deposits and no mold - you must or they will get mold!
 
Aqua Man

Aqua Man

26,480
638
I grow in a low Rh environment (30-45%) during the winter and I just don't consider it to be that big a deal (no lanky plants or poor yields). I mean, yeah I end up with some crispy dry leaves ect and I have to water often but the low Rh doesnt seem to have such a large negative impact that I would want to try to artificially introduce more humidity via humidifiers. Humidifiers can bring some negatives of there own with things like mineral deposits (unless you run RO or distilled water) and molds. I haven't used them for a grow but I have seen some really gross humidifiers that I wouldn't want anywhere near my living space, never mind my growing area. To each there own. I'm not criticizing anyone for trying to get their environment into more ideal conditions but like everything else, there are potential negative issues that don't get much discussion.
Disclaimer: my temps are low as well. Every time I see the VPD chart, all I can think is how I would be really concerned with getting PM if I was in that sweet spot.
Just gonna say the vpd charts you find online are the reason people who use them end up with pm. They are most often flat out wrong. When using VPD it is crucial to take leaf temps into account and ensure your humidity is not spiking after your lights go out due to temp drop. While you can grow in lower RH conditions there is a noticeable difference in growth. This becomes even more pronounced when using optimum light levels and you should never use anything other than distilled or RO water for humidifiers. Running a high VPD causes stress to the plants.

So yes it can be done and still get decent bud and yields but it will not be as good as if plants are grown under ideal conditions.
 
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