How cold is to cold? - New Growers - International Cannagraphic Magazine Forums

Tiresmoke19 · 03-20-2018, 01:09 AM

I made a set up for starting plants in jiffy pots.
It's a very big plastic tote with heating mat. The 3" jiffy pots and the led grow light I have fitted to top of lid. The heat sinks and fans from light are on outside of lid since I assumed it'd get to hot.

Did a trial run and with lights off, just pad on it gets down to 42 degrees.

With light on it stays at about 56 degrees.

Our ambient air temp in this barn is about 32 degrees

Can I start my seeds or is this to cold?

707OGBUSH970 · 03-20-2018, 01:17 AM

No. You really cant. I mean, it is possible that some might, but this would be the lowest end of the spectrum. You should be able to achieve some insulation with a heat source..that would be the only thing...at about 60, some will start to pop, but thats the zone for mold and other nasties. Heat and oxygen are what you need...you can actually achieve heat with even a candle in a small area, but you are asking for trouble. There are ways if you are careful, but that is too cold.

707OGBUSH970 · 03-20-2018, 01:18 AM

Im only a forum newb...LOL...

Tiresmoke19 · 03-20-2018, 02:15 AM

Kinda figured it'd be to cold. I assumed that tub would hold more heat, maybe I'll add another heat pad

Wendull C. · 03-20-2018, 02:48 AM

It is way too cold. Wait for your night time lows to be 45 and above. No reason wasting, or if you can keep em alive, stunting seedlings when only a lil patience is needed. Imho.

troutman · 03-20-2018, 02:51 AM

If the ambient temperature is that cold you should have waited for it to get warmer.

Anything below 65F will result in very slow growth.

If you can, bring it all inside the house for a few weeks.

igrowone · 03-20-2018, 03:00 AM

i'm growing in temps like those right now
it's growing, not as fast as if it was 70, but i'm fine with it

aridbud · 03-20-2018, 03:54 AM

Just think if your feet were exposed to cold temps....similar to roots. They don't grow until it's warmer, the soil warmer. Too, jiffy pots notoriously acidic. You'll learn.....

Tiresmoke19 · 03-20-2018, 05:08 AM

I didn't actually put seeds in the starting medium yet. Just trial running to see where Temps and rh ended up.

Yes I've used jiffy pots for other plants around the home farm. Our soil here has very high ph (basically on a big lime stone deposit) so the jiffy low ph isn't much of a factor. Tomatoes always worked well so thinking weed should do fine.

I'll be starting a second batch for some other lands where I'll need to bring up ph and will skip the jiffy pots for that run and stick to solo cups.

Tiresmoke19 · 03-20-2018, 05:16 AM

As far as soil temp, is there a magic number for marijuana seeds? I read various different air temps but never see any soil temps mentioned.

Our field corn we always wait till soil hits 50 degrees, and beans @ 55 degrees.

03-20-2018, 01:09 AM	#1
Tiresmoke19 Member Join Date: Mar 2018 Posts: 51	How cold is to cold? I made a set up for starting plants in jiffy pots. It's a very big plastic tote with heating mat. The 3" jiffy pots and the led grow light I have fitted to top of lid. The heat sinks and fans from light are on outside of lid since I assumed it'd get to hot. Did a trial run and with lights off, just pad on it gets down to 42 degrees. With light on it stays at about 56 degrees. Our ambient air temp in this barn is about 32 degrees Can I start my seeds or is this to cold?
	Quote

03-20-2018, 01:17 AM	#2
707OGBUSH970 Newbie Join Date: Apr 2015 Location: In a cave up in the hills... Posts: 7	No. You really cant. I mean, it is possible that some might, but this would be the lowest end of the spectrum. You should be able to achieve some insulation with a heat source..that would be the only thing...at about 60, some will start to pop, but thats the zone for mold and other nasties. Heat and oxygen are what you need...you can actually achieve heat with even a candle in a small area, but you are asking for trouble. There are ways if you are careful, but that is too cold.
	Quote

03-20-2018, 01:18 AM	#3
707OGBUSH970 Newbie Join Date: Apr 2015 Location: In a cave up in the hills... Posts: 7	Im only a forum newb...LOL...
	Quote

03-20-2018, 02:15 AM	#4
Tiresmoke19 Member Join Date: Mar 2018 Posts: 51	Kinda figured it'd be to cold. I assumed that tub would hold more heat, maybe I'll add another heat pad
	Quote

03-20-2018, 02:48 AM	#5
Wendull C. Senior Member Join Date: Nov 2012 Location: Where the peaks meet the sky Posts: 1,370	It is way too cold. Wait for your night time lows to be 45 and above. No reason wasting, or if you can keep em alive, stunting seedlings when only a lil patience is needed. Imho.
	Quote 3 members found this post helpful.

03-20-2018, 02:51 AM	#6
troutman Seed Whore Join Date: Dec 2016 Location: In the Fridge Posts: 1,603	If the ambient temperature is that cold you should have waited for it to get warmer. Anything below 65F will result in very slow growth. If you can, bring it all inside the house for a few weeks. __________________ I just died.
	Quote 2 members found this post helpful.

03-20-2018, 03:00 AM	#7
igrowone Senior Member Join Date: Jun 2009 Location: NY Posts: 3,980	i'm growing in temps like those right now it's growing, not as fast as if it was 70, but i'm fine with it __________________ current grow: www.icmag.com/ic/showthread.php?p=7872194
	Quote 2 members found this post helpful.

03-20-2018, 03:54 AM	#8
aridbud automeister Join Date: May 2013 Location: the best place on earth Posts: 5,589	Just think if your feet were exposed to cold temps....similar to roots. They don't grow until it's warmer, the soil warmer. Too, jiffy pots notoriously acidic. You'll learn..... __________________ Seeds have the power to preserve species, to enhance cultural as well as genetic diversity, to counter economic monopoly and to check the advance of conformity on all its many fronts. Michael Pollan Happiness held is the seed; Happiness shared is the flower. John Harrigan Instant gratification takes too long. Carrie Fisher - RIP. *afterthought autos* We are passionate breeders of unique quality cannabis autoflower hybrid seeds at down to earth prices; now 11 years running! https://www.icmag.com/ic/forumdisplay.php?f=65770
	Quote 2 members found this post helpful.

03-20-2018, 05:08 AM	#9
Tiresmoke19 Member Join Date: Mar 2018 Posts: 51	I didn't actually put seeds in the starting medium yet. Just trial running to see where Temps and rh ended up. Yes I've used jiffy pots for other plants around the home farm. Our soil here has very high ph (basically on a big lime stone deposit) so the jiffy low ph isn't much of a factor. Tomatoes always worked well so thinking weed should do fine. I'll be starting a second batch for some other lands where I'll need to bring up ph and will skip the jiffy pots for that run and stick to solo cups.
	Quote

03-20-2018, 05:16 AM	#10
Tiresmoke19 Member Join Date: Mar 2018 Posts: 51	As far as soil temp, is there a magic number for marijuana seeds? I read various different air temps but never see any soil temps mentioned. Our field corn we always wait till soil hits 50 degrees, and beans @ 55 degrees.
	Quote