Seedlings @ 65F

[The70’s]

Anyone else grow in these temps, my seedlings look fine, but im just soooo reluctant to add heat to my tent during this fragile phase, the risk of fire is my concern.


Woukd you add some kind of heat ?

 

[Retireegrower]

I have a radiant heat heater i use in my RV that has a low temp setting of 68*. If it was me in that situation I would probably run that. But, take my response with a grain of salt. I'm like the biggest NOOB and am just starting to learn. 35 years ago I thought I was a grower, but now that I'm back growing for the first time since then I realize the growers of today know a million times more than we did when we dug a hole in the ground and put in our seedling in and fed it with a garden hose.

 

[Carcass]

Woukd you add some kind of heat ?

I'd sit them on a seedling mat- if the soil is toasty warm, the tent temps don't matter as much..

 

[Delps8]

Anyone else grow in these temps, my seedlings look fine, but im just soooo reluctant to add heat to my tent during this fragile phase, the risk of fire is my concern.


Woukd you add some kind of heat ?

"the risk of fire is my concern."

I'd fix the issue that's given you concern about something catching fire.

65° is cold for cannabis. It won't kill the plant but metabolic rates fall as temperature declines. Another issue to think about is that water temps in hydro should not fall below 65 because uptake of P is starts to falloff at 64°. If you ambient temp is 65 I'd guess that your soil temp is going to be about 65 so you might run into a nutrient imbalance.


This is the famous graph from the Chandra paper on CO2, that widely misunderstood to claim that there's little benefit to putting high light levels on cannabis plants (that's a separate discussion).

Of note for this discussion is how low net photosynthesis ("net P") is when ambient temps are 20° (68°F). It's as low as net P is at 40°C (104° F). By raising the temperature from 68° to 77°, net P looks, to my eye, like it doubles. And things get downright frisky at 30 (86°F).

The net P value is a significant driver of growth of the plant because photosynthesis is the only way plants can generate food and which, in turn, is a driver of growth.

 

[KBUENOS]

Anyone else grow in these temps, my seedlings look fine, but im just soooo reluctant to add heat to my tent during this fragile phase, the risk of fire is my concern.


Woukd you add some kind of heat ?

Hey Friend, 65 is perfect, during germination the higher temperature really helps, after this however 65 to 80 degrees is the range that your plants need to thrive. That was a good question, many people might be informed thanks to you asking. have an awesome day ok.