judgment day (frost ariveth)

[slartibartfast4]

Well it was cold this morning as expected so i was out taking photo's of my frost covered babies this morning and will take a look this evening after work to see how much damage was done and will post some images for people who have yet to face the white monster this year.
One thing i really notices was the huge variation in temps on a very small scale , some areas less than a couple hundred feet apart varied by as much as seven degrees c and over my entire field and swamp temps varied by 11 deg from a high of +3 in the well flooded swamp to a low of -8 in the ditch in front of my house, the house thermometer at a proper 4 feet of hight registered -2 and the plant i have in my coldest spot suffered through -5 so it will be intresting to see damage this eve as well as the success or failure of my varied frost mitigation techniques.
Slart

 

[glock23]

yikes...good luck! hope it doesn't cause too much damage. i've never had to deal with frost...lucky me huh?

 

[CannaBuddyTHC]

Yeah PLEASE post pics i need to know about how frost can damage my girls!

 

[slartibartfast4]

Well so far the news is good, pretty much all the plants are looking good with very little damage. even the ones that took -5 look great and i will try and post picks tommorow. bottom line nothing damaged by -2 and only minor fan leaf damage on ones in colder parts so i would say relax about the frosts.
Slart

 

[slartibartfast4]

ok not used to the posting pics thing yet but i did upload 4 to my gallery last night if you want to take a gander one shows the temp, one shows a 7 am photo of one of the good size girls (the greeen frost free area in her center is where i sparayed her with water to compare damage when frost was melted off instead of sublimating naturally) and there is a picture of her in the evening showing minor famage to a few fan leaves. also a pic of a little frost covered tip (whish those where trichs. Try to post some later but been crazy busy this weekend.
Slart

 

[slartibartfast4]

ok an attempt at pic posting









Ok pic one is how i wished a plant would look due to trichome coverage , pic two is of thermometer showing the nasty temps and pic three is a plant that i had misted the middle of to melt frost in an attempt to mitigate damage from sublimation and the last pic was taken in the evening showing the same plant and just how little damage occured. for the rest of my plants i used a few different frost protection methods and all round damage is very slight . I will take some more shots this afternoon but bottom line is a couple degrees below freezing had no affect major effect on any of my clones or seedlings. This will help me rest easy in the future
Slart

 

[oldsterone-OG]

Outstanding pics. I live in Minnesota, and cold is somewhat of an issue. Gorgeous photos of what they really can take.

You have added to our knowledge.

I am going to take mine to the edge this year...naturally, the indica family can go futher than something from the tropics.

 

[vhGhost]

outstanding first pic.. i love it.... even tho its frost.lol.... what i'm wondering is what kind of damage other than to much moisture does a mj plant get from frosty weather... reason i'm asking is because i live in an area where i'll be happy if my plants can make it to 25th of oct. 50-60 days of flowering!

again nice job .. keep it up she's a trooper

oh btw any experts out there have a way of protecting these baby's? as long as possible against the frost ?
oh .. hehe me and a bud where talking about this.... what if you grew a monster plant harvested and left it in the ground untill next year... would it reveg... and get bigger every year ? we could grow Tree's .. hehehe treehouses..

 

[slartibartfast4]

well i had a field day trying frost protection on a lot of my plants and learnt more on that frosty night than i have in my last three years growingcovered a few with bags and they all look the same as those uncovered , the swamp is the warmest spot with nary a bit of frost in the area however i was impressed with tarping, the tarping on its own gives a degree or two of frost protection but i also put 4 tee lights under the tarp as well and they raised the temp to 7 deg a whopping 9 degrees above the ambient air temperature . and don't forget most of the damage from frost comes from sublimation in the morning simply washing the buds down with water to melt the frost around sunrise can work wonders. as for the frosty little guy in the above pics here are a couple i took today.








ok the first is a reminder and the last photo shows the worst damage i saw.
Slart

 

[slartibartfast4]

and as for leaving a monster plant to reveg i can't see that working unless min temps stay above -7-10.
slart

 

[SmokeyTheBear]

man, where do you live in im new york and im not expecting a hard frost for another month. light frost usually don't hurt my babies.

 

[vhGhost]

smokey i'm almost betting canada

 

[slartibartfast4]

Yep good old canada , just a bit west of ottawa generally our temps run a good five degrees colder than ottawa and i tend to follow the forcast from pettawawa as its lows are more in line. don;t think i will worry till predicted temps hit -4 this year so hopefully a couple weeks left . By the way for most annual plants the magic temperature for growth is a daily mean of 5 deg C if you stop getting that for a while most growth stops. Good luck to al the other cold weather growers and i sure am happy i set a lot of seed this year.
Slart

 

[BACKCOUNTRY]

I will see if I can get Stoner133 to come check this out, he has done pretty extensive experiments in South BC with how much cold a plant can take. That seems to be getting pretty cold there!!

 

[Stoner133]

Thanks for the heads up BC.

Great observations start, they pretty well match my own experience.

Some plants are very sensitive to frost, tomatoes, beans, peppers will all die off at 0C/32F. Other plants, those with concentrations of sugars that act as antifreeze can take lower tempetures still.

A couple years ago, we were comparing the effect of cold on our plants. My test plant demonstrated -7C/11F was beyond the recovery horizon. The plants that took -5C/25F could recover is conditions warmed up quickly. They can't take more then a day or two of that low temperature without serious damage.

The first image is my frozen solid plant. The plant is compared to control plants kept above freezing.... it was done.

The third image is my -5C/25F test plant. I wasn't planning on a second test, but the weather man missed by 6C that day. The plant survived, but it was a hermi and not worthy of keeping.

Covering them during a forecast frost is helpful, I have a frost blanket of lightly woven plastic material. It will get my tomatoes through a couple degrees and would do the same for Cannabis. It is removed early in the day, taking the surface frost and condensation with it.

 

[slartibartfast4]

Hello Stoner long time no see we used to occasionally talk cold weather back in OG days nice to see you are still around and thanks for dropping in.
Slart

 

[slartibartfast4]

well a guick update that good size BBxEG here she is again


well some of the buds that where not washed down before the sun hit them are showing signs of minor tissue damage so i harvested about 12 buds today just in case they go mouldy still pretty impressed with the frost tolerance and misting in the morning works wonders.
Slart

 

[vhGhost]

thnx for the update i'll keep my eye on this thread .. i'll post some pics when frost first hits here.... like i said before hopefully not till oct 25ish lol

 

[lookimrory]

well a guick update that good size BBxEG here she is again


well some of the buds that where not washed down before the sun hit them are showing signs of minor tissue damage so i harvested about 12 buds today just in case they go mouldy still pretty impressed with the frost tolerance and misting in the morning works wonders.
Slart

im a little confused sbf4, you say your woried about mold damage, but you mist your plants when they have frost on them. wouldn't this just promote the mold? i understand that you dont want the frost to just stay on there, but misting them with water seems like it would do more damage than its worth?

 

[slartibartfast4]

well in my part of the world mold is not a huge issue but mould does like to get it's start in damaged plant tissues, by misting i am reducing the risk or major frost damage and therfore tissue damage and it is the damaged tissues that will staart to rot first. in my parts as i said mold is rare and unless it has a reason to move in it won't and in the past i have found damaged (frozen cellualar damage) is a magnet to further decay. while some misting is no big deal.
Slart