Humidity Levels

[PassThatChronic]

FIRST OFF . . . please dont hate cuz i suck at spelling . . .

Hey guys, I just had a simple question and i was hoping to hear an answer from some of the people who have grow logs on here (cuz i know your information is correct).
I have recently been arguing with a few grow colleges about the humidity levels when the plant is in the 12/12 bud cycle. One college(advice A) says 30-45% is perfect and another college(advice B) tells me to jump it up to 70-85%. Right now i am trying to raise the humidity up to 75% and going with advice B. I just have a gut feeling that the humidity levels need to be dropped down durring bud cycle because when you first start a seed or even clone, you want the humidity levels way high. I always thought early life high humidity and when they get bigger (12/12 bud cycle) you drop it down to stop mold issues.
I honestly do not have an answer because i have never tried either one. Someone please give me an answer WITH facts on why, it would really help imp:

PassThatChronic Reviewed by PassThatChronic on 11-25-2008. Humidity Levels FIRST OFF . . . please dont hate cuz i suck at spelling . . .:( Hey guys, I just had a simple question and i was hoping to hear an answer from some of the people who have grow logs on here (cuz i know your information is correct). I have recently been arguing with a few grow colleges about the humidity levels when the plant is in the 12/12 bud cycle. One college(advice A) says 30-45% is perfect and another college(advice B) tells me to jump it up to 70-85%. Right now i am trying to raise Rating: 5

[Mr. Clandestine]

I don't have any grow logs here (yet), but 70-85 RH seems a bit steep to me. Different people like different humidity levels for different reasons; temperatures, C02 usage, etc. Personally, I keep mine between 40-60 during most stages of growth. Any less than that and it seems to affect the growth and health of the plant, any more (at least in flowering) and the buds seem to be much more susceptible to mold.

Just my :twocents:, for what it's worth.

[xxxhazexxx]

in grow or flower NEVER let your humidity go above 60 you need to keep it close to 50 in the growing stage and 40-45% in flower :thumbsup:

[killerweed420]

You can go to 100% humidity if you want. The issue is air circulation. The higher the humidity the better air circulation you need.

[Mississippi Steve]

As a Master HVAC tech, I can tell you that the *IDEAL* situation is 75F @ 50%RH. This will give you ideal conditions and will keep you from having any mold issues with the plants and buds. there is a very narrow bell curve where molds and viruses will *NOT* grow. With the ideal being 75F @ 50%RH, you can only go 5% either way. Use the most accurate measuring instruments you can afford, then find a psycometric chart and plot your temp and RH.

My grow temps range from 78 - 80F with RH at 45 - 50%. It plots out on the the chart to the equivelant of 75 @ 50%.

If you want healthy, this is the way to go.

FWIW, a good instrument to start with is digital sling psychrometer/thermo hygrometer. Its a combination meter that does Relative Humidity, Dry Bulb temp, Wet Bulb temp, and dew point, and reads in either F or C. They are around a hundred bucks, and are accurate enough for me to do my job with.

[the image reaper]

I agree with Mississippi Steve's advice :thumbsup:

[PassThatChronic]

Thanks, things are looking about 75%F and 55% humidity when hps light is off and when its on.(thanks to fans, heaters and humidifiers) I do not plan on letting anything go above 80%F or 60%humidity