Humidity

[Hashsloth]

Along with the other ideas suggested above you can hang a wet towel with one end in a bucket of water and blow the air from you fan across it in the tent.



RH is one of the most important environmental factors in a high yield high quality grow. The stoma located on the plant leaves open and close based on the temperature and RH of the air around the leaf. If the stomata are closed transpiration is slowed or stopped. Transpiration moves the water bearing nutrients throughout the plant. If transpiration is not happening because the stoma are closed the plant cannot take up nutrients. This will lead to stunted growth and/or nutrient deficiencies. The ideal scenario is to follow VPD as close as possible. I live in a desert and it is nearly impossible for me to hit VPD most of the year. I shoot for and can remain >40% <65% RH most of the year. IMPO 30% is too low.

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I realize that cannabis grows better when its grown at a higher rh than 30 percent. But this guy has a humidifier going already and its not helping much.
I was just trying to tell him that he shouldn't worry about the humidity too much then,because good plants can still be grown with rh of 30 %,I've done it so it must be possible. Maybe I could've got an extra ounce or so if my humidity was higher,but I'm not going to stress too much and try to change how I do things over an oz.

 

[Mañ'O'Green]

I realize that cannabis grows better when its grown at a higher rh than 30 percent. But this guy has a humidifier going already and its not helping much.
I was just trying to tell him that he shouldn't worry about the humidity too much then,because good plants can still be grown with rh of 30 %,I've done it so it must be possible. Maybe I could've got an extra ounce or so if my humidity was higher,but I'm not going to stress too much and try to change how I do things over an oz.

Just like everything else genetics can be at play here. If you grow strains from arid regions of the world you may fare better at low RH but the science is with VPD.

 

[Delps8]

I realize that cannabis grows better when its grown at a higher rh than 30 percent. But this guy has a humidifier going already and its not helping much.
I was just trying to tell him that he shouldn't worry about the humidity too much then,because good plants can still be grown with rh of 30 %,I've done it so it must be possible. Maybe I could've got an extra ounce or so if my humidity was higher,but I'm not going to stress too much and try to change how I do things over an oz.

If you're able to grow at 30%, more power to you. Me? Not a chance I'd grow something at that level.

30% RH is about ½ the recommended RH. If you look at a VPD chart, a grower has to go to extra ordinary lengths to come even close to an acceptable value. Photosynthesis isn't the only issue. With humidity at that level, transpiration rates take off and that can cause nutrient issues due to the significantly increased water uptake.

If there's nothing the OP can do about it, well, that makes it easy - he's just got to suck it up. OTOH, why not stack the deck in his favor and create an environment where the plant can thrive rather than just survive?

My tuppence.

 

[Death The Cultivator]

An unintended consequence of dry conditions, where a plant may be weakened due to uptake issues and excessive transpiration, is that it becomes a prime habitat for pest.

 

[Davie-e]

Along with the other ideas suggested above you can hang a wet towel with one end in a bucket of water and blow the air from you fan across it in the tent.



RH is one of the most important environmental factors in a high yield high quality grow. The stoma located on the plant leaves open and close based on the temperature and RH of the air around the leaf. If the stomata are closed transpiration is slowed or stopped. Transpiration moves the water bearing nutrients throughout the plant. If transpiration is not happening because the stoma are closed the plant cannot take up nutrients. This will lead to stunted growth and/or nutrient deficiencies. The ideal scenario is to follow VPD as close as possible. I live in a desert and it is nearly impossible for me to hit VPD most of the year. I shoot for and can remain >40% <65% RH most of the year. IMPO 30% is too low.

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Thanks, this is the stuff you need to know like!! I’ve got it sorted now like it sits between 55-65 Celsius now, never goes above 70 or below 50, what do you think, are these are ok numbers ?

 

[Bob's Auto's]

Thanks, this is the stuff you need to know like!! I’ve got it sorted now like it sits between 55-65 Celsius now, never goes above 70 or below 50, what do you think, are these are ok numbers ?

Perfect! Maybe for young seedlings a bit higher, but nothing that can't be solved with a humidity dome

 

[Mañ'O'Green]

Thanks, this is the stuff you need to know like!! I’ve got it sorted now like it sits between 55-65 Celsius now, never goes above 70 or below 50, what do you think, are these are ok numbers ?

You do mean RH and not celcius? Yes thos numbers will work until mid to late flower when just above 40% RH is good.

 

[Davie-e]

You do mean RH and not celcius? Yes thos numbers will work until mid to late flower when just above 40% RH is good.

What would you say about mixing liquid seaweed with the canna Nutes?

 

[Rick Dirte']

Thanks for all the info MOG. I am redoubling my efforts to raise my humidity. I filled my trays with water and set a small fan down low
blowing across the trays. Also just ordered another larger humidifier. What a pain in the rear! I do want those fat buds though lol.

 

[Bob's Auto's]

I do want those fat buds though lol.

Who doesn't???