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seeds nighttime germination temps

Hi everyone, I'm new to the forums. I posted in introduce yourself earlier this morning.
 
I've started off with a nice variety of peppers. I have a seed heating mat, a 2'x4' 4 bulb T5, and am using the two cup method with red cups and plastic bags over the top to germinate my seeds. Most of the info I am seeing says 80-85° is the ideal temperature for germination. Do I want to maintain this temperature 24 hours a day?
 
Right now the heat mat and the light are keeping me in that range, but the light is only on from 6am to 6pm (I know seeds don't need light to germinate, but helps the temps a bit).
 
Is there a temperature the seeds should be dropping to at night to stimulate a day/night and does that have any effect on germination?
 
I am growing
 
Red/orange/yellow Scotch Bonnet
Jalepeño
Ancho/poblano
Chocolate Bhutlah
Cayenne
BBG7 Yellow
Red Moruga
DEFCON 7
 
I have some other seeds on the way - cascabel, shishito, Reapers, and Bahamian Goat.
 
Here are some pics of the setup in my garage. Since this picture was taken I've moved the heating mat inside the tub rather than under it. Looking forward to some input and hope to get a great first crop later this year!
 

 

 
 
austin87 said:
Hi everyone, I'm new to the forums. I posted in introduce yourself earlier this morning.
 
I've started off with a nice variety of peppers. I have a seed heating mat, a 2'x4' 4 bulb T5, and am using the two cup method with red cups and plastic bags over the top to germinate my seeds. Most of the info I am seeing says 80-85° is the ideal temperature for germination. Do I want to maintain this temperature 24 hours a day?
 
<SNIP>
 
 
 
 
 
Yes, until the seeds germinate, constant heat and humidity.
 
Welcome to THP!

That looks like a solid setup. 80-85 is ideal, but people germ successfully in much less than that. If it drops even 10 at night I think you'd be okay. I did mine at a constant temperature because I used a heat mat thermometer, but in nature they'd normally see a day/night cycle. Either way works.

Good luck!
 
Well crap. It seems like I over adjusted, I checked the soil temps and they crept up to low 90s.
 
I unplugged the mat and will look at a thermostat for it. This morning they were very cool, so tonight I think the plan is to cover it with a towel and plug the mat back in...
 
It was foolish of me not to test this out more thoroughly before planting...
 
yea going right onto the heat mat can be an issue.  I thought I cooked a batch of bell pepper seeds that didnt germ after 2 weeks.  Tupperware was right on the heat mat.  Took it off the mat and 2 days later all had hooked(of course AFTER I had re-started an entire new batch...).
 
If you cover the mat with a towel then put your stuff on top of it, the mat is likely to heat up really hot.  I also found that out.  Without a thermostat they are supposed to raise the temp ~20 degrees over ambient(at least thats what mine said).  Well when the sensor heats up because its wrapped in a towel it just keeps getting hotter and hotter.
 
 
What I did(and I germ in tupperware with wet paper towel) is to elevate my tupperware off the heat mat about 1" with some spacers.  Worked like a charm to bring up the temp, but not get to hot and possibly cook the seeds.
 
Low 90s I wouldn't worry about.  Just do not keep them that high now that you realize.  Peppers, while difficult to germinate, are still pretty resilient.
 
With that being said, a thermostat, or a temperature controller is nice to have.
 
I suggest you keep the night temps constant, just like day time temps.
 
I think the lights are unnecessary while the seeds are still waiting to germinate. The heating mat is good enough. 
 
I am new to germinating my peppers from seeds, so i will not pretend to know remotely close to what others will suggest. That said here are my obversations of my experience thus far, I have good to great success with keeping my temp at 25°C/77°F. During the night I found my heating pad struggled to even reach 18°C/65°F so I a crafted a makeshift dome or cover if you will from some foiled bubble wrap I had lying around hep hold the heat in the domed tray. That brought my night temps in line with what I wanted.
 
If anyone is having issues getting the stuff above the heat mat warm enough get some home insulation and stick it under. This makes it significantly more efficient, just make sure the heat can rise up; if it's trapped on both sides that will lead to problems.

I got a 1, maybe 1.5" thick pink board from Home Depot with an R value of like 5 or 5.5 - something like that. Works great. Kept the stuff nice and warm and protected the surface I put it on.
 
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