How cold is too cold???

[AhighPIPER]

My veg room is in an unfinished basement, and it's been dipping down to 58 degrees F when the lights are off. Is this a problem? What are the signs of cold plants?

 

[Secret Jardin]

they can turn purple and growth slows down.

 

[greenpeace31]

open a heat ducket up and warm them up

 

[Shootngbear]

i would imagine if your night time temps are that low, then your humidity will be far too high aswell, a small oil filled radiator will solve your problem...just put it on a timer to come on as your lights go out.

 

[Secret Jardin]

i would imagine if your night time temps are that low, then your humidity will be far too high aswell, a small oil filled radiator will solve your problem...just put it on a timer to come on as your lights go out.

I grow in my basement aswell and I get in the 50s also at night. and my RH is 27%. I actually have to but a pan of water in my tent to raise the humidity.

 

[Resin225]

I have the same problem. I put some 1/2 dense foam and 1/2 plywood on the floor. Brought my temp up to65 from 58, during lights off. I also run my light from 7 pm to 7 am. to help offset the cold. I'm in flower I'll take the 25% RH.

 

[AhighPIPER]

So its not necessarily a problem? They do look a little droopy for the first hour or so once the light turns on, but no purple stems or leaves.

Actually the lower temp the lower the humidity.

I grow in my basement aswell and I get in the 50s also at night. and my RH is 27%. I actually have to but a pan of water in my tent to raise the humidity.

I seem to have the opposite effect. When my lights are off my humidity goes up to 60-65, when there on it goes down to 30-35.

 

[Resin225]

do you run a fan in the room during dark time? Are you in soil?

 

[AhighPIPER]

I have the same problem. I put some 1/2 dense foam and 1/2 plywood on the floor. Brought my temp up to65 from 58, during lights off. I also run my light from 7 pm to 7 am. to help offset the cold. I'm in flower I'll take the 25% RH.

Thanks for the info. I got em on folding table to keep the pots off the concrete. That might be what ill have to do, change there light cycle so there on at night.

Nope, I have my fan turn off when the lights do. there in soil also

 

[Resin225]

Heating cold air up causes it to dry out, that may be why your rh drops when the light comes on
The rise in rh could be from the moisture from the soil or dwc system. Running a fan will help with that, it did for me.
I was afraid the temp would go down with the fan on but since I have insulate the floor, I have a fan on top and below the plants. I was surprised that my temp stayed the same.

You could put a space heater near your intake if thats possible.

 

[Resin225]

Thanks for the info. I got em on folding table to keep the pots off the concrete. That might be what ill have to do, change there light cycle so there on at night.

You can get the pink dense foam insulation at Home depot for about 10 bucks. I put the plywood on top so I could slide my buckets easier. It made my temps go up by 7 degrees.

 

[woodsmaneh!]

So its not necessarily a problem? They do look a little droopy for the first hour or so once the light turns on, but no purple stems or leaves.



Its is a problem because if you are trying to get the most growth you won't get it that way. I bet the floor temp is even lower that the air temp? Put some ridged foam under them, don't be cheap get the thick 2, 2 1/2 stuff.If your vegin you need to get the temp up into the 65 + to make the most out of the next growing day. Same for Flower. Run the lights at night or get a small ceramic heater with tip over protection. About 20$ at wallie mart.

 

[AhighPIPER]

Heating cold air up causes it to dry out, that may be why your rh drops when the light comes on
The rise in rh could be from the moisture from the soil or dwc system. Running a fan will help with that, it did for me.
I was afraid the temp would go down with the fan on but since I have insulate the floor, I have a fan on top and below the plants. I was surprised that my temp stayed the same.

You could put a space heater near your intake if thats possible.

Good idea, Ill keep my fan on tonight and watch the humidity. +rep

So its not necessarily a problem? They do look a little droopy for the first hour or so once the light turns on, but no purple stems or leaves.



Its is a problem because if you are trying to get the most growth you won't get it that way. I bet the floor temp is even lower that the air temp? Put some ridged foam under them, don't be cheap get the thick 2, 2 1/2 stuff.If your vegin you need to get the temp up into the 65 + to make the most out of the next growing day. Same for Flower. Run the lights at night or get a small ceramic heater with tip over protection. About 20$ at wallie mart.

Im sure the floor temp is colder(its concrete). I have the plants up on a folding table about 3' off the ground. Ill run my lights tonight, and if its still to cold ill cough up and get a heater. good advice +rep

 

[Resin225]

If you are in veg are you at 24/0 or 18/6? the reason I ask is that you should start your 12/12 time at the same time your lights come on @ 18/6. If you need to get your start time to say 7pm from 7am, you would want to do that in veg if possible. Gotta be picky once you go to 12/12. Be sure you have 0 light leaks before you enter flower.. GL..

 

[Heads Up]

Where I live, the humidity goes up at night. My room, the humidity goes up at night. When your temps drop into the fifties is when you have to take steps to prevent it from happening constantly. A ten degree or so drop is recommended when your lights go off. I use a dehumidifier which runs all the time and an air conditioner, which I leave set at seventy one and keep it on energy saver. I also purchased an oil filled radiator type heater, they are superb. From everything I've read soil temps of sixty eight are recommended. Plant growth actually slows with temps in the sixties and will bring out different colors in your plants. I'm a couple weeks away from being done and I'm purposely trying to lower my temps at night without getting them to low to bring out some color. Two of my plants have responded by turning some of their leaves a lovely purple.

 

[AhighPIPER]

If you are in veg are you at 24/0 or 18/6? the reason I ask is that you should start your 12/12 time at the same time your lights come on @ 18/6. If you need to get your start time to say 7pm from 7am, you would want to do that in veg if possible. Gotta be picky once you go to 12/12. Be sure you have 0 light leaks before you enter flower.. GL..

Im vegging on 18/6. Off at midnight, on at 6 am. Does this mean I have to run my 12/12 from 6am-6pm? My flowering and veg rooms are 100% light tight.

1st pic-veg room
2nd+3rd-flower room

 

[AhighPIPER]

Where I live, the humidity goes up at night. My room, the humidity goes up at night. When your temps drop into the fifties is when you have to take steps to prevent it from happening constantly. A ten degree or so drop is recommended when your lights go off. I use a dehumidifier which runs all the time and an air conditioner, which I leave set at seventy one and keep it on energy saver. I also purchased an oil filled radiator type heater, they are superb. From everything I've read soil temps of sixty eight are recommended. Plant growth actually slows with temps in the sixties and will bring out different colors in your plants. I'm a couple weeks away from being done and I'm purposely trying to lower my temps at night without getting them to low to bring out some color. Two of my plants have responded by turning some of their leaves a lovely purple.

Congrates heads up!! +rep You just made your 420th post in my tread. All good info, im gonna have to make some adjustments. Ive got a huge old ass furnace like 10' from my grow. Maybe I can open a port some were so it heats the basement?

 

[Heads Up]

I must be stoned, it reads 421 to me. I didn't even notice. The info is courtesy Jorge Cervantes indoor grow bible.

 

[Greg1919a4]

lower your light to about 12 to 18" from top of plants

 

[Jtoth3ustin]

mine go down to around 55 lights off. but as long as you keep um at 70-75 lights on. then you dont stress them that much getting used to the colder temp.