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What Range Should I Maintain For My Growroom Humidity & Temperature?

Baja Big Dog

New Member
What about water chillers and radiators on the lights? Anyone have experience with them?
 

PuffNPass

New Member
My humidity is at 25-30% with my temp at 82. I shut off my basement de-humidifier and started running a humidifier. It's much cooler in the basement now and maybe a little more moisture but haven't seen humidity in my grow cab above 35%. I'm using a 55cfm for intake and 105cfm for exhaust. The veg/clone chamber is 12 cubic feet. Any suggestions???
 

bahoona

New Member
burnt marijuana

Hey guys me and a friend just built a grow room and forgot to ventalate and when we checked on our babies they had shrivelled leaves and looked horrible. we now have ventalation and the room isnt as hot but the weed isnt getting any better :( please help?!!!! should be pluck the shitty leaves or somthing ....... agh soo scared!
 

freedomring1

New Member
Daytime conditions should be 70-80 degrees without co2, 80-90 degrees with co2 until the last two weeks when daytime temps should be kept between 70-80 and co2 can be reduced to adjust for the lower metabolism. Night temperatures should be kept above 60 degrees to prevent stress. It is preferrable during flowering to have a night temperature drop of 10-20 degrees to stimulate flowering hormones and reduce stem elongation.

I find that low humidity causes stress on plants. I recommend 50-60% humidity until the final 2 weeks of flowering. At this point, the humidity should be lowered as much as possible to encourage the plant to seal and protect itself with additional resin. (I am able to get the humidity to go as low as 31%) I have been able to frost things up considerably this way. The higher humidity levels prior to final ripening reduce salt levels within the plant tissue and encourage healthy, more lush growth.

Author: MisterIto

I am expanding from a box op. to a 10x10 room op. and I was told that I still need co2, but if I keep the ac in the room set at 68' wouldnt it be the same thing?
 

311roller

New Member
I have 2 temp gauges: the first one on the wall of my grow room underneath the filter and fan via a reptile sticky thermometer, the other I have a digital thermometer with a cable. I have the cable underneath the light. the temp under the filter is between 70-80, but the digital thermometer that is reading the temp under the light gets to right around 85. is this ok?
 

jdabs

New Member
What would one expect ifor the quality of the crop if their running a constant 71 degree's and 42% humitity during the 24 hour light cycle? I'm about 4 days out from pulling the trigger to a 12/12.

This is my first go at this.

I'm running one 600 hps, 2 t5 6bay 54t835's 3500k spectrum

25 plants one table.

I'm assuming the temp is going to drop 10 degree's during the night cycle.
Feeding 15 minutes every hour.

Neutral Cubes for growing medium.

Any advice or input would be greatly appreciated.

p.s. In Alaska so it's pretty dry and cold up here, temp and humidity are my main concerns. How much do I lose with the above circumstances if all the rest is good?

Thanks in advance.
 

Baja Big Dog

New Member
What would one expect ifor the quality of the crop if their running a constant 71 degree's and 42% humitity during the 24 hour light cycle? I'm about 4 days out from pulling the trigger to a 12/12.

This is my first go at this.

I'm running one 600 hps, 2 t5 6bay 54t835's 3500k spectrum

25 plants one table.

I'm assuming the temp is going to drop 10 degree's during the night cycle.
Feeding 15 minutes every hour.

Neutral Cubes for growing medium.

Any advice or input would be greatly appreciated.

p.s. In Alaska so it's pretty dry and cold up here, temp and humidity are my main concerns. How much do I lose with the above circumstances if all the rest is good?

Thanks in advance.
You never vegged at 18/6?

How big are the plants?

25 plants on one table? Thats a lot of plants, age you planning on thinning them out? Im no expert, but thats a lot of plants for a little light!

Once an hour watering...seems like a lot to me also, lets get some input from others..I water 6 times a day, for 20 minutes, two weeks into 12/12 with a ton of buds, 6 plants under 1000 watts, and its crowded, very crowded!!

Keep us informed...
 

jdabs

New Member
I got the plants from a friend who veg'd them, not sure what the his schedule was. He had them for about 6 weeks prior to bringing them over.

Size wise: I have about 15 that are 2 1/2' tall, 10 at 1 1/2'.

I was planning on trimming the bottom 6-8 inches on each plant tomorrow.

Regarding the light I have one 600 hps in the center of table over 9 plants and 1 6bay t5 on either side of that taking up the outer 8 plants on both sides.

Room is completely "N.A.S.A'd" up...all shiny.

Once again, first time here for me. Looking for any input and help.
 

Tulip

New Member
The temperature is the hardest factor to take control of to me. When confined to a small space, ballasts and lights can push temperatures sky-high in no time flat. That is why I use CFLS, to avoid venting heat. This is especially true during hot summer months when outside temperature reaches its highest. Nighttime (LIGHTS OFF period) temperature can be just as difficult to regulate during cold winter month. Most gardeners are aware that temperature in the grow room plays a major role and can greatly affect the growth of plants and the quality of the finished crop. Most gardeners do not know how controlling the temperature of their garden in very specific ways they can achieve a superior crop. Drift to far from these ideal temperatures and watch your plants and crop suffer.
Before getting started it is highly recommended that every indoor garden has a max/min thermometer. (Digital $5.95 at Walmart)

This product allows the gardener to see exactly the fluctuations in temperature within their garden. Without this useful tool there is no accurate way of knowing the different temperatures between daytime (lights on) and nighttime (lights off). The difference between the two temperatures is very important to plant growth. Anymore than a 10F-15F difference between daytime and nighttime temperatures and you risk shocking and stressing the plants. You want a 10 degree difference between LIGHTS ON and LIGHTS OFF temps. In general the optimal daytime temperature for plant growth is between 70F -75F. Drift to far above this range or too far below and growth can be severely affected. Daytime temperatures exceeding 90F or under 62F and plant growth will be slowed and stunted. Plants do thrive in afganastan's 110 degrees, but they almost quit growing at that temp. If the temperature drifts higher than 95F the plant's enzyme production will drop off and the plant will begin shutting down. At temperatures above 92 - 94, high photosynthesis shuts down due to the stomata in the leaves closing down to conserve water. At normal temperatures the stomata will be open, taking in CO2 and sweating water to keep the plant cool and allowing for transpiration.
Ideal temperature varies depending on whether or not CO2 is being introduced to the environment. A more suitable daytime temperature when the air is being enriched with CO2 is 80F-85F. This temperature range promotes the exchange of gases between the plants and the environment. Also, it can speed up the process of photosynthesis. Plant in an environment at 86F can perform carbon extraction from CO2 twice as fast as at 68F. It is still recommended that the nighttime temperature drop no more than 15f from that of the daytime temperature.

There is another relationship between temperature and the absorbsion of gases by plants that many hobbyist growers are aware of. That is the relationship between the temperature of the water in your reservoir and the amount of oxygen the water can hold. The best range that your reservoir can be between is 60F-75F. Ideally the reservoir temperature should be at 65F because this level contains the most oxygen. Also this temperature will help control transpiration (the act of drawing up nutrients by evaporating water through out the leaves), and humidity levels. Buying a simple aquarium floating thermometer will allow you to know where you fit in this range.


$2 to $4 at Walmart, Target,
PetSmart Aquarium Dept


Another great reason for regulating the temperature in your grow room is that biological processes can be speed up exponentially by every degree. This is true for your plants as well as the potential pests that may invade your grow room.
Pests such as spider mites can reproduce up to 10 times faster with every degree the temperature rises.
These pests can destroy a garden in no time flat, you really do not want to make it any easier for them. Spider Mite Eggs and webs can screw up the buds so bad, they can nto be smoked. With a daytime temperature at a steady 72F and nighttime temperature of 65F it is much easier to control and destroy spider mite, thrip, and many other pest populations.
The same principal can be applied to the prevention and control of fungi, molds, mildews, and bacteria, which can spread more rapidly when temperatures in the grow room or reservoir exceed 90F. Also, the warmer the air, the more water it can retain which means humidity levels can easily go beyond the recommended 40-50% for Vegging. (you want high humidity for VEG, and low humidity for Flowering.) This high humidity coupled with lower nighttime temperatures can cause condensation to form on leaves. This will invite molds, mildews, fungi, and bacteria to take over you grow space. With high temperatures the likely-hood of losing control of the problem, such as powdery mildew, is very high. Once control is lost your plants may be the next to go.

Temperature is also very important when it comes to starting seeds and getting cuttings to root. Placing seedling trays on a heating mat will reduce germination time dramatically. Speeding up germination time usually leads to stronger and healthier plants. Also, less time spent between crop cycles makes a garden efficient. More harvests provided in less time can equal big bucks in the pockets of professional growers.
The ideal temperature for sprouting or cloning is 80F. Any higher and you risk burning the roots. Also, many seeds simply will not germinate at temperatures over 90F. The seeds will become dormant and never sprout.
The same principal used for seeds is used on cuttings to coax roots out quicker. The sooner cuttings can establish roots the better. If roots can be forced quickly they will grow strong and stay strong. A bottom temperature of 80F-85F, roughly 10F warmer than the air, will speed up rooting time and help to jump start those roots once they do begin. Let the temperature get too high or too low and roots growth will be hindered or they will never grow at all. Using the proper technique and the proper temperature for bottom heat not only can rooting time be speed up from 2 weeks to as little as 3 days, but the survival rate of your cuttings will drastically improve.

On the topic of roots, there is an ideal temperature for the root zone after the plants' roots have been established. Roots are working 24 hours a day and constant attention is required concerning temperature in and around the root zone. The ideal temp for this root zone is generally 65 to 75 degrees F. At this temperature the ion exchange between the roots and the environment around them is at its absolute best. This means that the plant's root system can take up more macro nutrients, more micro nutrients, and more oxygen at this temperature than at any other level. This makes a plant more efficient and a plant working efficiently will provide a superior yield.

Amazingly, some growers grow successfully with no themometer for the air or water. But for maximum efficiency, you got to take control of temps.

HUMIDITY? that is more simple to me. Get the Humidity VERY high for VEGGING, and very low for FLOWERING.

in Vegging, I mist them daily. I do raise the lights up, to be careful with my bulbs getting wet and breaking. And when it rains outside, it also gets cloudy and the sun's rays are blocked. Plants in outdoors, in nature do get an ocasional rain shower or thunderstorm. Do you let it rain on yours? I do, but artificially by MISTING.
AND, I bought a cheap humidifier at Walmart for $26..

REMEBER, During Flowering, we need a low humidity, especially to avoid Bud mold and bud rot.
 

Baja Big Dog

New Member
Holy crap Rose, that some good info in some good ole plain engrish!!!

My nighttime temps go to 90 with the lights one 12/12, and Im using C02, and the daytimes are running about 75, the 90 sounds like its bordering on a problem, but Im two weeks into bud, and the plants are really going off, but my humidity is below 40 most of the time.....


So for so good....
 

Woodsman

Plant of the Month: Oct 2010 - Member of the Month: Mar 2010, Jan 2011
Hi folks, Speaking of cooler indoor temps (with lights 70 deg and in the dark at 60 deg), I've been anxiously awaiting for my 1 Mazar Afghan to mature enough to harvest. I'm at 10 1/2 weeks flowering using 1-100w hps and 2- 23w cfls started flush two weeks ago with distilled water and molasses (100 percent cloudy trichs) . Growth now seems to have slowed down with only 10 percent amber trichs and maybe 60 percent red hairs. Is the long flower time a product of my avg. low temps or low wattage?
 

Woodsman

Plant of the Month: Oct 2010 - Member of the Month: Mar 2010, Jan 2011
Thanks jdabs,
I also have not been checking the ph as this is a pretty simple grow (low budget) although looking to be quite a fruitful one! I've grown before without checking for ph and never had issue. I only use distilled water and ff ferts at 1/2 to 3/4 strength. Very basic grow. Just thinking that maybe the temps being cool would slow things down. First time with Mazar Afghan which of course a mostly indica F1.
As you see I've tried unsuccessfully to post a photo. I just requested some help on that issue to the photo people.
 

Woodsman

Plant of the Month: Oct 2010 - Member of the Month: Mar 2010, Jan 2011
Wow Joe Coffee, Thanks for getting my photo up there. was that in response to my request to 420 or did ya just do me a big favor? Anyway thanks, I don't know why I haven't been able to do it myself?
 

Woodsman

Plant of the Month: Oct 2010 - Member of the Month: Mar 2010, Jan 2011
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