how cold does it have to be to kill a plant

South Texas

Well-Known Member
I've got a Baby that popped up in my "Kiddie Pool worm farm" where I threw dis guarded seeds. It got down to 28, that Baby is still kicking ass. The rim blocks the north wind, and it has full south sun all day. The 28 may have only been an hour or so. I would not have believed it, if I didn't see it for myself. Strain is Afghan. 40 degrees will hardy up the plant. But the soil must be warm to do this.
 

RachelRay

Active Member
growth starts to slow when the temp gets below 50 F

im sure plants can survive at 40 degrees F like some people said, and im sure a lot of that depends on the strain

but i wouldnt recommend going too far below 50 with any plant unless youre sure its able to tolerate those temps because it will impact the growth.
 

Bubba Kushman

Well-Known Member
Pot plants dont die unless they freeze. At 65 degrees growth almost stops to protect the plant. The growing range is 65-85 degrees anything out of this range and growth pretty much stops till back in range. But it wont kill the plants.
 

socalkushman

Well-Known Member
once the plant freezes...say goodbye.. i had a couple RIP from dropping below 32.. couldnt handle the mountain cold
 

Orange Shovel CAGrower

Well-Known Member
the plant only dies if it goes below 32 degrees. since water freezes at this temperature, the plants will die because the majority of the plant's vascular system is made up of water.
 

chromer

Well-Known Member
Hey guys, I've noticed lots of posts about frost worries since i joined the site a while back.. at this time of year its right up there with the "hey guys, is this ready to be harvested?" (which is almost always 'no').. but i digress.. living in southern Ontario, we have our share of cold nights and there have been frost warnings 3x in the past week or so (and i honestly dont lose a wink of sleep over it).. it's something we have to deal with so here are some tips for other people who are worried about frost killing their crop

#1.. don't worry.. just cause your blazed out of your tree and you start getting paranoid that your plant(s) is gunna turn into an icicle overnight doesn't mean you should run outside at 2am in your boxers to cut the bitch down 2 weeks before it's ready to be cut..

#2.. in my experience, it actually HAS TO FROST before damage is done to your plants(AND, IMO i've had light frosts that haven't hurt my plants at all).. i live in Canada, i know the difference between cold and freezing, 36`F/2`C is fine for your plants, THEY WONT FREEZE.. YOU are the one who should chill out

#3.. plants can handle the cold weather, unless you live in NorCal (or somewhere else warm) and theres a freak cold snap, your plant will be conditioned to handle cool temps (ie, mid to high 30's/1-3`C).. marijuana is hardy, u dont have to baby it.. like I said, if the temp doesnt get below 32/0` there wont be a problem..



OK, so now on to the actual problem.. the forecast is calling for a frost.. WHAT DO I DO???


Again, before you go outside in your boxers at 2am to cut down your babies, be proactive..

#1 rummage around your house (or even the salvation army) and get some old blankets/bedsheets (i don't trust garbage bags).. wrapping burlap around your plants also works

#2 water the ground around your plant(s).. the moisture will evaporate and be released into the surrounding air around your plants, raising the humidity of that air.. thus making it physically tougher for it to freeze and making it tougher for the plant to 'freeze'

#3.. gently put your bedsheets/blankets over the plants, it's easiest if you have stakes around your plants so the plant itself doesn't have to bare the entire load..
During the night, the ground will release heat that will be trapped by the blanket, keeping the inside of the blanket warm relative to the outside :smile:

#4.. get up early, check the thermometer, it'll prolly read above freezing (unless you get up at 3am) and take those conspicuous blankets off.. you should be ok



Still worried that they got frosted??

Spray cool-cold water on the plants, this will thaw them out without shocking the leaves/buds (which will happen if you spray them with hot water)


Hopefully that solves some uneasiness in the forums.. maybe it'll even solve one persons' problem.. if it did, then i did my job :smile:

:peace:

if i missed something or u have a better/different technique, by all means, add it
 

dexster25

Active Member
ya thanks that helps alot but yaa it wont get that cold here its california not detroit hahhah so ya sweet sweet

but how can i protect my plant from drowning from the rain any ideas
 

Arby Bones

Member
10/01/22....
I am at 2000ft elevation in northern Vermont...a wicked short season..even with good south facing plot. I have had plants live thru 30-31°f. without covering. It kicks em, and often they will finish ripening faster.
We are due for 27°f tomorrow night, and that's cold...as cold as i have left them out...but I am not too worried. I will gently wrap the branches with jute...kinda like a Christmas tree for transport....I call it huddling...then I put tall wood stakes on 3 sides and cover with at least 2 heavy contractor bags, alternating the bottom...now the top... seam directions, and then use a less conspicuous green sheet. Plastic trash bags alone, just transfer the cold thru, and the tops or any other part of the plant unlucky enough to touch the plastic do pay hell for it.
Around midnight, I will usually go out and warm(ish) water the plants. I'll even put a hot water gallon under the sheet for the colder nights, as well. This will get me into mid October, sometimes to the 3rd week.
It is nerve-wracking after the tree leaves have fallen, but I don't tell the plant when it's ready to harvest...I have to wait until it tells me, and none of them have even mentioned it yet....sigh...the tri's are still 'glass clear' on everyone but my autoflower OG Kush.
I'll pop back tomorrow, and let you if I have potsicles, or not.
 
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VolimPicke

Well-Known Member
Last night it was 5c (41 f) and my plants are not dead
Tonight it will be 3c (37 f) and I doubt my plants will die
- in Toronto area
 

Arby Bones

Member
10/01/22....
I am at 2000ft elevation in northern Vermont...a wicked short season..even with good south facing plot. I have had plants live thru 30-31°f. without covering. It kicks em, and often they will finish ripening faster.
We are due for 27°f tomorrow night, and that's cold...as cold as i have left them out...but I am not too worried. I will gently wrap the branches with jute...kinda like a Christmas tree for transport....I call it huddling...then I put tall wood stakes on 3 sides and cover with at least 2 heavy contractor bags, alternating the bottom...now the top... seam directions, and then use a less conspicuous green sheet. Plastic trash bags alone, just transfer the cold thru, and the tops or any other part of the plant unlucky enough to touch the plastic do pay hell for it.
Around midnight, I will usually go out and warm(ish) water the plants. I'll even put a hot water gallon under the sheet for the colder nights, as well. This will get me into mid October, sometimes to the 3rd week.
It is nerve-wracking after the tree leaves have fallen, but I don't tell the plant when it's ready to harvest...I have to wait until it tells me, and none of them have even mentioned it yet....sigh...the tri's are still 'glass clear' on everyone but my autoflower OG Kush.
I'll pop back tomorrow, and let you if I have potsicles, or not.
Follow up....everybody is fine, healthy and happy. It hit 27 that night, and when I uncovered them in the morning, within 45 minutes, they were back to normal, and have turned some beautiful colors in the last couple of days.
 
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