Seedlings starting at 60 degrees F ?

[St. Phatty]

My indoor temps run from 55 degrees at night to 60 degrees plus in the day, under lights.

Is this TOO hard on seedlings ?

I could use a small heater to keep the temps up in the indoor grow room.

 

[I'mback]

Raise the heat in your house!

 

[Guest]

That's too low. I like 80 deg. temps with RH in the 70s for seedlings. Leave your lights on 24/0 to keep the heat up or small heater. Not saying it's impossible with those low temps, but sure lowers your odds.

 

[Dropped Cat]

Thermostat controlled seedling mat.

Maybe 40 bucks plus a heat mat.

Cheaper than losing beans to chilly soil.

 

[AgentPothead]

I got https://www.amazon.com/gp/product/B010GNW6T8/ that used to be a listing for a heatmat + thermostat, but now it seems to just be the heatmat. I have to use them for my seedlings, I put the probe into a rapid rooter and put it with the plants so it has the same rough temperature, set it to turn on if it gets down below 75F.

 

[WelderDan]

They'll grow a hell of a lot faster with even 10 more degrees. Get the temp up to at least 70 at night. A cheapo ceramic heater will be enough. Just don't put it to close and start at lower settings

 

[Betterhaff]

You can get quite a bit of heat from an incandescent bulb, especially in a small enclosed space.

 

[TychoMonolyth]

Yes it'll work. But they'll be really slow.

I start a lot early spring in a shed. It has power, but no heat. I use this heated throw/blanket for a heating mat under thin piece of plywood. I paid $15 on Kijiji for a used one but you can get them on Amazon.

I can get 500 starts on it no problem.

https://www.amazon.ca/Sunbeam-Chica...ocphy=1002342&hvtargid=pla-448848868310&psc=1

 

[aridbud]

Invest in a small space heater. Roots and plants liker balmy temps. If on a cold concrete floor, a germination mat would keep the roots happy. Once seedlings are stronger remove the mat. Pallets on concrete work, as well.

 

[St. Phatty]

Thanks for all the replies !

I remember the fastest sprouts I ever had was Orange Crush, from BCGA.

Cali-O x Blueberry.

5/5 sprouted in 24 hours, i.e. climbing above the rockwool.

3/5 were females, in that first batch.

That was in San Diego so house temp was 70+.


Remember that scene in Breaking Bad where Walter White gets pissed off at his assistant for setting a piece of equipment at 75 instead of 85 ?

Walt says, "this is CHEMISTRY. Degrees matter." Or maybe he said, temperature matters ?


UPDATE -
Moved the seedlings into a closet that had a 250 watt metal halide with a fresh bulb.

It's about 4 feet by 6 feet and 9 feet high.

Temp stabilized at about 74.

House temp is about 60.

The 12 pack is an extreme frosty Indica crossed with the 2019 heat / drought resistant Sativa male.

The 10 pack is Blueberry Headband, crossed with Blue Widow and about 7 other strains. Crossed with the same male.

The thermometer thing comes in really handy. It's a cheap plastic one that came with an egg incubator.

The cat just dug up a Creeping Myrtle that was much larger than a Cannabis seedling. Got to keep him off the plants.

 

[St. Phatty]

Update

Nature finds a way

6 out of 10 sprouted in the tray on the left.

Room at 73 degrees F, which feels positively toasty.

 

[Teddybrae]

Phatty, we go by Celcius over here and I haven't got a conversion chart handy, but ...


My Colombian Sativa used to germinate outdoors in the mulch around my Citrus at 19C. That's probly 60 something F. It was still winter.

 

[I'mback]

20 deg C = 68 deg F

 

[St. Phatty]

The temperatures are running 75 to 80.

Feels nice and warm.

Plus a picture of some Medicine.

I will end up probably transplanting them twice.

They're in quart yogurt pots now. I can fit them all in the Veg. room if they go into gallon pots.

Before I move them to the main room, they have to be big enough to withstand the cat's friendly behavior. Biting and clawing.

I'm pretty sure the cat likes the cannabis because the cats have cannabinoid receptors just like people.

 

[theJointedOne]

raise them up off that carpet at least. seedmats are your friend, just dont put the temp sensor in moisture, somewhere dry gives best readings

 

[GMT]

Its winter in the UK here. My night temps are cold, as in below 10 c. My plants are fine, flowering girls to seedlings to cuttings. May be a little slower, but plants don't die because of a bit of cold. Not saying its ideal, just its not a concern.

 

[St. Phatty]

A few Plants up to 3 or 4 Nodes.

Added the Bucket of CO2 today.

The Cannabis Cat has been banished.

It's hard to take pictures of bubbles !

It's like a super-bubbly bottle of champagne, 1 gallon. It lasts for about 3 days then slows down but keeps producing CO2.

The recipe for the small batch -

1/2 gallon warm water
2 teaspoons active dry yeast
1/2 teaspoon Champagne or Wine yeast
1 1/3 pounds sugar, trying to make a 4 pound bag last 3 batches of CO2.

I saw the chemistry once. They said it worked out to about 1 pound of CO2 for every pound of sugar that goes in.

It's under a 250 watt Metal Halide, with about 3 months of use on the bulb. Temps are now 75 to 80 F.

 

[Insomniac420]

My room here is 21c to 23c humidity 80%
I leave lights on 24/7 helps keep temps stable
Good luck with your grow

 

[St. Phatty]

My room here is 21c to 23c humidity 80%
I leave lights on 24/7 helps keep temps stable
Good luck with your grow

Thanks !

I spaced out and poured the sugar water solution on one of the seedlings. And I'm not sure exactly which one (that's the spacing out part).

So I moved the CO2 bucket out of the way, but still in the room.

Then I'm thinking not to worry, it's just sugar water.

 

[Raho]

It's colder at night than in the daytime. That's when you should be running your lights.