Growing with LED in cold climate

MidnightSun72

Well-Known Member
yeah heat mats... or do what i do,.... liquid cool the leds and run that water into a container inside the tent or a reservoir under the plants, with a few vents, you might need to reinforce that if done underneath. if you have enough lighting you should be able to keep them warm and humid. then get a thermostat to regulate your exhaust fans. 200-300 watts of leds heat dumped into a 15 gallon tank should keep them about 70 degrees and 50% humidity. obviously you will have to top it off every so often. and if you are going to do this you can probably used cheap leds and make your own. as you will probably need the heat spare the lighting efficiency.
Maybe I didn't tell exactly what I want to ask...
I know about LEDs need higher temps than HID/HPS, I actually own DIY Samsung Q strips and have experience about it... But in almost perfect environment, so above 27°C, catching VPD, heaters, coolers, humifiders, etc...

I am asking if it's possible (and if plants can be healthy) to grow in 15°C with LEDs, if anyone did it in practice. I guess leaf temps would be at 10-12°C. And what's about feed then, if they transpire less than they would at 27-30°C. I guess feed has to be adjusted to lower temp. But again... can be done at those temps?
Any pics of your liquid cooling setup? No rad just recirculating the water?
 

Brettman

Well-Known Member
Lots of peeps are using them but they require a heater in colder climates, if you don't want the expense of heating on top of the actual led price use hid.
Only problem with that is you still have the cold night time temps.
 

Wastei

Well-Known Member
Grow with hydro. My rooms hardly never got over 24C/75F during winter months. You gonna need some heating of some sort during lights out.
 

Brettman

Well-Known Member
Anyone done it?
How low did you get with temps?

My garage stays at 10°C, tent at 15°C year long. I guess I need new place because this is too low for LEDs...
I’m up North and grow in a cold basement. I was running 500w in a 3x3 with temp swings 62-85. I recently changed to 300w and added a 200w heater and now my temp swing is 75-80. Plants seem MUCH happier now.
 

KonopCh

Well-Known Member
I’m up North and grow in a cold basement. I was running 500w in a 3x3 with temp swings 62-85. I recently changed to 300w and added a 200w heater and now my temp swing is 75-80. Plants seem MUCH happier now.
How's that possible?
500 W is 500 W.
 

Brettman

Well-Known Member
The heater is two settings 150 & 250watts. It might be on the 150 setting. I also played around with my exhaust because at first it went up to like 87f.
 

Florere

Well-Known Member
Anyone done it?
How low did you get with temps?

My garage stays at 10°C, tent at 15°C year long. I guess I need new place because this is too low for LEDs...
Yes. They need a ec of 4,5 in my situation

Temperature around 20 in the wintertime
 

ScaryGaryLed

Well-Known Member
i recently put a small heat pad under my tent, like 25W i think it is. and it's working really really well. Temps in my basement are around 60 when it's 20 degrees outside. i didn't think it was going to make much difference but the roots and growth have exploded and now I will transplant one last time and start the flowering in about 1 week. Hopefully they are all ladies. I'm not sure if a heat that blows hot Air is the best idea. Mine actually was getting to locked up for a minute with water. (too little then too much) a small tent fan on low setting seems to be helping them absorb the water better. Possibly too much light too. I'm using about 120 watts in a 5 ft square area. im going to reduce them a little to get about 3000 lumens per sq foot. that should help them strect out a little. Seems like too much intense light can be a bad thing too. FYI using 3000k cobs. 158 lumen/watt at that 120 wattage.
 

Rocket Soul

Well-Known Member
i recently put a small heat pad under my tent, like 25W i think it is. and it's working really really well. Temps in my basement are around 60 when it's 20 degrees outside. i didn't think it was going to make much difference but the roots and growth have exploded and now I will transplant one last time and start the flowering in about 1 week. Hopefully they are all ladies. I'm not sure if a heat that blows hot Air is the best idea. Mine actually was getting to locked up for a minute with water. (too little then too much) a small tent fan on low setting seems to be helping them absorb the water better. Possibly too much light too. I'm using about 120 watts in a 5 ft square area. im going to reduce them a little to get about 3000 lumens per sq foot. that should help them strect out a little. Seems like too much intense light can be a bad thing too. FYI using 3000k cobs. 158 lumen/watt at that 120 wattage.
How big is the pad?
 
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