Is 30% humidity enough

RichED

Well-Known Member
:shock: Hello all Im new to the game all of a month and a half experience, got the nerve for my first grow Jan 3rd 09. After spending lot bucks on weed I graduated High school in 1967 and started smoking weed in the 10th grade. Anyway I have a 39 square grow tent with starter adjustable flouresent and a 100 watt cfl in it. It has a four inch duct with inline fan takeing the exaust to my tiny flowehr closet fourteen inch by thirtysix inch with a 250w hps and conversion mh.
The closet takes care of the exhaust for both I have a small carbon filter inside and another larger inline fan and a largecarbon filter outside the closet. I have a humidifyer in the grow tent runs about 65% fine by the time air gets to the little closet it is at 30%. the closet has three six week old babys in it, Is that enough to get by? Oh yeah tempature in both 72 - 75.
muchthanks
 

longlizard

Well-Known Member
A study showed humidity was a factor in sex determination. Greater humidity created more females. Coolness and Nitrogen also helped determine female plants. Where as dryer, hot, and potassium helped incur males. More humidity might not hurt during the immature stage. Though to high of humidity during flowering might cause mold.
 

longlizard

Well-Known Member


http://www.marijuanagrowing.com/article.php?sid=30
Humidity Humidity is relative, that is, air holds different quantities of water at different temperatures. Relative humidity is the ratio between the amount of moisture in the air and the greatest amount of moisture the air could hold at the same temperature. In other words, the hotter it is, the more moisture air can hold; the cooler it is, the less moisture air can hold. When the temperature in a grow room drops, the humidity climbs and moisture condenses. For example, an 800 cubic foot (10 x 10 x 8 feet) grow room will hold about 14 ounces of water when the temperature is 70 degrees F and relative humidity is at 100 percent. When the temperature is increased to 100 degrees F, the same room will hold 56 ounces of moisture at 100 percent relative humidity. That's four-times as much moisture! Where does this water go when the temperature drops? It condenses, just like dew condenses outdoors, onto the surface of plants and grow room walls.
A 10 x 10 x 8 foot (800 cubic feet) grow room can hold:

4 oz. of water at 32 degrees F.
7 oz. of water at 50 degrees F.
14 oz. of water at 70 degrees F.
18 oz. of water at 80 degrees F.
28 oz. of water at 90 degrees F.
56 oz. of water at 100 degrees F.
Relative humidity increases when the temperature drops at night. The more temperature variation, the greater the relative humidity variation. Supplemental heat or extra ventilation is often necessary at night if temperatures fluctuate more than 15 degrees F.
Cannabis Clue – The moisture holding capacity of air doubles with every 20o F increase in temperature.

Cool your grow room is thats kind, for females.
 

longlizard

Well-Known Member
Cannabis grows best when the relative humidity range is from 40 to 60 percent. As with temperature, consistent humidity promotes healthy, even growth. Relative humidity level affects the transpiration rate of the stomata. When humidity is high, water evaporates slowly. The stomata close, transpiration slows and so does plant growth. Water evaporates quickly into dryer air causing stomata to open, increasing transpiration, fluid flow and growth.
Warning! Air that holds 16 ounces of water at 75 degrees F will hold only 10 ounces at 60 degrees, causing 6 ounces of water to condense out of the air into the room.
Transpiration in arid conditions will be rapid only if there is enough water available for roots to draw in. If water is inadequate, stomata will close to protect the plant from dehydration, causing growth to slow.
Measuring Relative Humidity
Relative humidity control is an integral part of insect and fungus prevention and control. Humidity above 80 percent discourages spider mites but promotes fungus, root and stem rot. Humidity levels below 50 percent reduce the chances of fungus and rot.
End of Excerpt
 

RichED

Well-Known Member
much thanks to you I need to make a change dont know where yet my little closet is very small like 14x36x48 once again much thanks
 

MaDz

Well-Known Member
A study showed humidity was a factor in sex determination. Greater humidity created more females. Coolness and Nitrogen also helped determine female plants. Where as dryer, hot, and potassium helped incur males. More humidity might not hurt during the immature stage. Though to high of humidity during flowering might cause mold.
Not sure about that... I'm growing 6 babies in humidity 15%, 30deg. Celcius and had 5 females on 6 plants... I think it's only a Gen thing and a bit of luck ;)
 

shadowdarker

Well-Known Member
if you find that the humidity is too low cover the babies with a clear persrex box or something of the sort. this way the humidity within the lil green house u just made will rise and babies love high humidity hope this helps . happy smoking
 
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