humidity

[LLL214]

hey peeps, I got this HUMIDITY PROBLEM
I have a 12x6x8 foot shed lined with plastic , a 250 w MH ,one 4 foot shop lite (2 florescent tubes )one 35 w led tube lite ( suppose to be equal to 100W) ,two 90W CFL ,two 90W led bulbs, .
I have elect. 900W-1500W heater plus a 450W PHOBOLIC heater.
I have a VICKS vaporizer ,plus a COOLMIST PROCARE ,I tried the COOLMIST PRO first, and the humidity was only 20 % to 27 %,,so I added the VICKS VAPORIZER to the set-up, still only 20% - 27% .
I have to go through three doors to enter the room,plus raise the plastic liner to get into grow room. I spray the plants with H20 every day, I water once a week ,I fertilize evey other week. My heat average is 70o .I have two fans one small suspended from ceiling,the other bx fan on floor. I own 18 acres, so privacy is no problem. Of coarse ,any help is apprietiated..

 

[Chunkypigs]

Whole house humidifier.

 

[Douglas.Curtis]

Average temp is 70F, drop it to 68F and you're golden. Expect terpene rich plants which do not stretch like a kale plant on a super nitrogen feed. You'll have to veg longer for sure. High elevation cannabis grows at low temps and low humidity, just how I like to set up my own gardens.


One way to increase humidity is to increase the amount of plant matter transpiring water into the air.

 

[LLL214]

Average temp is 70F, drop it to 68F and you're golden. Expect terpene rich plants which do not stretch like a kale plant on a super nitrogen feed. You'll have to veg longer for sure. High elevation cannabis grows at low temps and low humidity, just how I like to set up my own gardens.


One way to increase humidity is to increase the amount of plant matter transpiring water into the air.

thanks,I live in ark.

 

[LLL214]

humidity

Whole house humidifier.

in a small room like mine,?

 

[troutman]

Temporary solutions to low humidity for small areas if you can't afford a humidifier is to either hang moist
towels and/or to set up a shallow tray of water with a fan blowing on the moist towels or tray of water.

 

[BC32]

Humidifier is the easiest way if you have the money. OR, check your weather and leave a couple windows open to bring in from outside, if this is even possible? I dont know the humidity there at this time or if you have ability to get fresh air to the plants quickly.

 

[Andyo]

ultrasonic misters

ultrasonic misters

i put 4 in a washing up bowl with a ball valve and used a cheap humidistat.

 

[CrushnYuba]

Possibly the easiest solution is to slow down how fast you are exhausting. Only exhaust as much as you need to provide c02. If you are having that much trouble with a room that size, you are probably exhausting more then you have to. Or you you have a serious draft.
Do you know about dew point and how relative humidity works? You are bringing in fridged air and heating it. For every 20 degrees you heat that cold outside air that comes in, relative humidity is cut in half. So let's say it's 80% rh outside and 30f, you being that air in and heat it to 70f, and the rh becomes 20%.

Whole house centrifugal humidifier that you can connect to a waterline so you don't need to refill humidifiers would definitely work. Put on a cheap humidistat if it's to much moisture.

Is it possible that your humidity guage is wrong? Those things Get wet one time and they are done. Pretty temperamental.

You didn't mention what your exhaust setup is. Are you just relying on a drafty shed? Not exausting at all?

 

[LLL214]

humidity

Possibly the easiest solution is to slow down how fast you are exhausting. Only exhaust as much as you need to provide c02. If you are having that much trouble with a room that size, you are probably exhausting more then you have to. Or you you have a serious draft.
Do you know about dew point and how relative humidity works? You are bringing in fridged air and heating it. For every 20 degrees you heat that cold outside air that comes in, relative humidity is cut in half. So let's say it's 80% rh outside and 30f, you being that air in and heat it to 70f, and the rh becomes 20%.

Whole house centrifugal humidifier that you can connect to a waterline so you don't need to refill humidifiers would definitely work. Put on a cheap humidistat if it's to much moisture.

Is it possible that your humidity guage is wrong? Those things Get wet one time and they are done. Pretty temperamental.

You didn't mention what your exhaust setup is. Are you just relying on a drafty shed? Not exausting at all?

so far the room which is lined with plastic has not got too hot, if anything 40o and 29% humidity added another heater ( phobolic ) kept both vaporizer and coolmistifier going24 -7 .. I cannot understand how a plastic bag could have a draft with two heaters running and door way closed,I got the heat to go to 80o ,but never got humidity above 49%
thanks for replies, I guess I will try to line the walls with Styrofoam and see If that will get me the humidity.

As far as a whole house humidifier I am not that rich , I am a poor cracker .

 

[Chunkypigs]

The whole house unit I got on Amazon was $120 and it works well and holds 6 gallons, I fill it once a day, my humidity in a poorly sealed room is now in high 30s to mid 40s.

The low 20s I was at a few weeks ago had some of my girls looking really effed up.

 

[CrushnYuba]

I keep asking you what you are using for an exhaust. Do you have an exhaust fan? Do you have a controller for it?

The only reason your humidity would be to low is because your exhausting too much or your shed has a crazy draft. Bottom line. There is no other cause. 2 humidifiers should be more then u need for a room that size.
Vent less, and heat less, humidity will go up! I promise.

 

[Douglas.Curtis]

The low 20s I was at a few weeks ago had some of my girls looking really effed up.

What was your canopy temp? One thing most people forget is how transpiration is used for both cooling and hydration. A small part is used for the movement of nutrients and good stuff, the rest is moving water.


When the humidity drops, your plants will increase their transpiration rate to stay hydrated. Higher transpiration rates require lower nutrient strengths. The plant is using the same amount of nutrients, but you need to help them by watering it down with all the sweat they're going to be pumping out to compensate.


CrushnYuba is right though (good job!), getting even close to a semi-sealed room will create humidity issues. The more plants you have, the more transpiration is going on and the higher your humidity will be. Slowing down your exhaust will quickly cause your humidity to rise.

 

[thailer]

this works for small grows all the way up to larger grow rooms. I've been using it for two winters and it raises my humidity around 10-20% in a two car garage. It can produce more or less because it uses single ultrasonic pond foggers which you can add to increase output or subtract. They can also be ran on a timer that turns off and on.

The best part about it is that I only fill the rez every ten days. It's incredibly easy and relatively cheap.


I purchased 3 single head foggers instead of a 3 head fogger because it was cheaper and I get the same output of 500 mL per hour for each single head while the 3 head puts out 1600 mL Each single head was $30 while the 3 head foggers were around $120.


So here's what you would need:

Container of any size for the rez. bigger means more time between refills (5 gallon to garbage can)
Ultrasonic pond fogger with kit that has float and power cord
Ducting of any size
Timer

The container I used was a garbage/recycle can I bought from Home Depot. I use 6" ducting so I cut a 6 inch hole in opposing sides of the container. This way I can put the duct in one hole and directly across from it is the passive intake. The humidity will suck up into the intake as air comes into the container.

Then after you get it all hooked up, find the lowest point of your ducting and poke a small 1/8" hole to let the condensation that builds up in the tube a place to escape so a puddle doesn't form in your duct. Put a catch pan to catch the drippings. this evaporates so you shouldn't have to empty it.

I've also used a 5 gallon bucket to place inside rooms i can't hook up to the intake or just small rooms/areas. i put it next to a fan so the water vapor escapes because it acts similar to dry ice fog. works awesome and you can get creative with the design.

 

[EagleWolf]

In my 12x8 room, I had to put three of those cheap "cool mist" ultrasonic humidifiers to get the RH up. I started using a humidifier for ipm, spider mites at the time. I stopped after powdery mildew. Now it stays around 20% and the plants are fine, over a year now. I got to agree with DC, if low RH screws with them, then your ppm's are too high.

 

[Douglas.Curtis]

Correct EagleWolf, you were seeing stress from excess nutes. Dropping your ppm allowed the plants to use a lot more water. You can drop your temps, or drop your ppm. Either way, the stress on your plants will be reduced.

I'd like to try some of your flowers some day.

 

[944s2]

As others have said and without spending big hen it's soaking wet towels, buckets of cold water,,,s
Lot of work but will help,,,,
Best of luck,,s2

 

[CannaRed]

Correct EagleWolf, you were seeing stress from excess nutes. Dropping your ppm allowed the plants to use a lot more water. You can drop your temps, or drop your ppm. Either way, the stress on your plants will be reduced.

I'd like to try some of your flowers some day.

What if you are in organic soil?
My temps with light off 67.
Lights on 81. Rh 20%
I can feed less on my Salamander Soil (fox farms coco mix) but I'm not really feeding my organic mix.

Great information here!
Thanks

 

[Douglas.Curtis]

The only issue I have with soil, is it really does better with a root zone temp of at least 72F. (Edit: The other issue is it's difficult to change the amendment amount. Increasing transpiration rates requires a lower amendment rate to prevent the same type of overfeeding stress.) With 20% RH, I'd want the air temp to be between 65F and 68F.

 

[EagleWolf]

Hey, wouldn't that be cool? I think I need more posts... Shouldn't be hard to arrange though, gotta love being in Colorado!