Indoor Max growing temp?

[SHRED]

What is the highest for temperatures in a grow space and still produce good plants?
I got a 315 LEC and initial tests have it a bit hotter than my old setup. I'm running low 80s pulling from an ambient temp of low 70s.
Going forward into winter my garage temp will drop so that will help plus I'll avoid daytime lights on.

 

[SporsNads]

I've had temps over 30c when I grew my Auto Candy Kush and it turned out well

 

[Grim Reefer]

Hi Shred
25-26c is the recommended temperature.

 

[Bamba]

With led you want to run a bit hotter, so 28-29C is the sweet spot.

LED-based light sources differ from sunlight and HID not only in their duo-chromatic, photo-synthetically tailored spectral output, but also in the fact that they produce virtually NO IR. So a plant growing in a room with HIDs at 78f will actually exhibit the metabolism of a plant at 83-85f, while the same plant in a room with LEDs at 78f will only have a 78f metabolism rate.

 

[TheSpacePope]

It varies by growers comfort level. Me and alotta people say so inside your tent and if it feels too hot for you, its to warm for your plants. An of course it does vary by plant genetics. But as long as your no pushing past 87f at canopy level or below 68 in night cycle you should be good but if your getting near there I would suggest watching the leafs. Canna plants with start to curl up on the edges indicating heat stress. But thats my two cents. GL brudda

 

[Gabro]

"Canna plants with start to curl up on the edges indicating heat stress"

So you see the plant bending sort of curling upward. Which is the way she transpires... So watch out for that. She will exchange water for temperature.

At that point if temperature reach a certaing point. The plant STOPS "WORKING" properly. So it stresses them. Their metabolism accelerates with temperature. But at a certain point It just fucks you up.

And the high temp is prone to overwatering. Which by itself opens the door for fungi if exaustion isnt proper.

So you better turn off the lights rather than keeping them 24/0 if the temps are high.

But one plant may differ from the other. When it comes to heatstress.

Accordingly to Jorge Cervantes (my guru) the max you would want is 30 celcius. But honestly, i grow sativas... they love sunlight and the days here reach nonsense temps... like 36...40 and even warmer. Plants sure dry out. But in the end, you water them and they recover "nicelly". If they could speak, they probably would ask for even more sunlight! XD

Damage for overwatering in other hand, is normally lethal.

Im under no circunatancy encouraging you to forget about the temps, when I mentioned my infernal warm days... instead, I suggest that the lamps coop down on the peak of high temps. Giving your girls some rest also.


Temps over 40~44 degrees (C) will cook your plants just like an egg fries and turn white.

Thats all I can assure by now!

Stay cool (literally)!

 

[Hal 8999]

I can depend. The brighter the light and stronger the nutrients, the more heat it needs. Think of it as late spring or summer. If you add silica that will give you an even higher extreme temperature tolerance. The same way that co2 enrichment only works at 80 F and above. With silica and plenty of nutrients, 90 F should be no problem. I do deep water culture in those temps with excellent results.

 

[Mudmenace]

IV had a few problems with my plants with nutra burn repotted them now on different soil and they alot happier after 24hrs but tent seems to run 35degrees quite happily IV being struggling to get the temp down even with 18/6 light pattern

 

[bartlancertp]

below 60F will stunt growth, and above 95F will lower quality. Low 80's is fine. I shoot for 76F for daytime (and rarely get it). You want at least a 10 degree difference between day and night.. My room gets as hot as 115F in the summer and my plants survive, though a much lower quality crop than spring and fall. Make the afternoon your light's night time, crank up the ventilation to lower temps.

 

[thomas m]

So here is what I think. First off everyone is going to be wrong. Every grow is different so variables always come into play. Start with growing strains that work well in higher temps. Any temp is fine as long as you have ways to cope. Some people use co2 some use silica. Point being I have grown in 100+ had no issues. If I had my way in a perfect situation I would stay arou d 75-79. However I typically run below 86 degrees. Turn out exceptional top shelf Every time.