Cloudz2600
Well-Known Member
More than a year later and no links, seems legit lol. Thanks for bumping this thread universe, gonna have to go with UB on this one.
Day/Night Temperatures
- Thread starter nizmo
- Start date
tommyromano
Active Member
Maybe we could do something about that.
Even though this document is on chrysanthemum's. The information that is contained inside relates to other plants. I've been searching the web for an document to post up and the best I can find is here http://aob.oxfordjournals.org/content/90/1/111.full.pdf
It all has to do with internode and stem length. also has if I remember correctly from my studies, anything drastic change within 10-15F WILL show symptoms of mild shock its system. same goes for the root system when you shock it from either warm or cold water.
Going back to what Uncle Ben had said. I would strongly disagree.
Plants don't do so well when the root system is cold. Matter of fact anything under 50-60 and the root systems metabolic uptake starts to cease up. When I say stay within 10-15F from your day/night, Even human's burn their own bodily nutrients to get the temperature to the level we need it at. Example: its 950F out and your you drink a cup of ice cold water, your body will now burn calories to get that ice water to the temperature your body is set at. So that being said, if your day is 75F and your night is 55F your plants priorities will be set to adjusting temperatures so it can run it's photosynthetic process and NOT on "growing" or "flowering" like you want them too.
If anyone has any questioned on this. just google "biochemical processes's of plants" and look into plants mechanisms for heat and cold tolerance and read about a plants metabolism when related to hot/cold.
Hope We Helped
BustinScales510
Well-Known Member
I have very little fluctuation with my temps..75-77 lights on..70-72 lights off. My plants thrive. Grows that Ive had before with lower dark period temps had bud rot issues, especially bushy indicas..so I like to keep it low 70s.
dozer777
Active Member
Growing purple kush currently. Temps have been much higher at night this round compared to last grow over the winter. Most of my plants with major temp variations turned purple 7 weeks in flower. I'm there now and there is no purple on any. They look good but, not the purple color going on that so many like. Including myself. Not that color is what it's all about. Let you all know on the potency.
tommyromano
Active Member
Hey, wonder if I can give some advice. Temps and your relative humidity have a large roll to play in the whole "botrytis" factor. BUT you may be having issues with air circulation. Do you currently have fans running? I mean blowing into your plants that is. If you haven't got oscillation fans to circulate the air and to blow cool air onto your plants, you WILL suffer bot rot issues. Your temps seem to be perfect, but you may need to check your humidity or check the air circulation. anything over 80 and you might have issues. But with your temps, I don't see why this has happened in the first place
dang... ive been keeping my nighttime temps around 75F. thought it might be too cold for it since the lights are off and the intake air is quite cold.
Maybe we could do something about that.
Even though this document is on chrysanthemum's. The information that is contained inside relates to other plants. I've been searching the web for an document to post up and the best I can find is here http://aob.oxfordjournals.org/content/90/1/111.full.pdf
It all has to do with internode and stem length. also has if I remember correctly from my studies, anything drastic change within 10-15F WILL show symptoms of mild shock its system. same goes for the root system when you shock it from either warm or cold water.
Going back to what Uncle Ben had said. I would strongly disagree.
Plants don't do so well when the root system is cold. Matter of fact anything under 50-60 and the root systems metabolic uptake starts to cease up. When I say stay within 10-15F from your day/night, Even human's burn their own bodily nutrients to get the temperature to the level we need it at. Example: its 950F out and your you drink a cup of ice cold water, your body will now burn calories to get that ice water to the temperature your body is set at. So that being said, if your day is 75F and your night is 55F your plants priorities will be set to adjusting temperatures so it can run it's photosynthetic process and NOT on "growing" or "flowering" like you want them too.
If anyone has any questioned on this. just google "biochemical processes's of plants" and look into plants mechanisms for heat and cold tolerance and read about a plants metabolism when related to hot/cold.
Hope We Helped
dammit... i dont know who to listen to. Uncle Ben said a 20F drop is good and high night temps eat up carbos. but you say it will shock the plant. guess i gotta go research myself. hopefully marijuana plants is just like any other plants when dealing with temps.
Uncle Ben
Well-Known Member
For starts, I wasn't referring to temps in the root zone. Yes, very cold temps at the root zone will impede normal processes.
Again, if you stray far away from mother nature's drills it will show up in various ways. If a plant is using the carbos it made during the day to excessive respiration then production or plant health will suffer. I could care less about internode length on mums.
http://aggie-horticulture.tamu.edu/ornamental/a-reference-guide-to-plant-care-handling-and-merchandising/light-temperature-and-humidity/
I consider cannabis just another annual foliage plant. Also, it's a di-cot.
I think you're splitting hairs as this issue is just one of many regarding general botany. I've been growing for decades. A night temp of 10 - 20F works very well. They just don't "thrive", they grow like weeds. See this thread as an example. I don't think there are many (soil or hydro doesn't matter) that can start a seed and 3 weeks later have a plant ready for flowering. Here's one such journal - https://www.rollitup.org/general-marijuana-growing/9114-spin-out-chemical-root-pruning.html
UB
My best friend recently went through this issue. He was running his lights at night and turning them off during the day. Everytime I would go visit them I would tell him, something isnt right man. I didnt know at the time that he wasnt turning his ac on during the day to cool it down. When I finally asked the right question (weeks later) it was of course too late for that batch. He fixed the issue after and the difference in the batch he has going currently and that last batch is 100% night and day difference.
You better believe a drop in night temps is important.
You better believe a drop in night temps is important.
Dendrophilly
Well-Known Member
My plants are feeling the temperature swing. Hoping for some purple. I think I see the start of it.
my lights are off during the day. and it gets around 78-82F. and when the lights are on during the night, its around the same temp. it should be a good thing to turn on the lights at night since its colder. but what should i do when the lights are off? winter is coming soon but daytime temps are still pretty high in california. is a portable giant AC ok to put in the grow room? i think the AC dehumidifies by sucking the moist from the air and make cold air from it. but it also vents out hot air from the back. i tried once to let the carbon exhaust suck the vented hot air, but it weakens the passive intake since it is using most of its energy sucking the hot air.
youngtrader9689
Active Member
lol. i have run sealded rooms for years now my temps are 83-85 day and no lower than 76 at night. i have huge colas. i have found out that my very stretchy ecsd plant will form nice big complete colas at these temps. But in my non sealed room the (76 day, 67 night) the same strain has more stretchy colas. the following pic is from sealed room. 
youngtrader9689
Active Member
those are 17 inch full colas. the non constant temp room has way larger inter nodal lengths EVERYTIME. (with the diesel) i used to use bushmaster to stop stretch, but there is no point if u manipulate your day/night temps. i cannot remember the exact details but its called temp. differential and it directly relates to floral and light stretch.
83-85 in the daytime? is this for flowering as well? shouldnt flowering be around 75-80?
Da Almighty Jew
Well-Known Member
Whatever happened to the old theory 68 at night 77 during the day?
Uncle Ben
Well-Known Member
High P foods induce stretch, if that's your worry. I just deal with what I'm handed and work with common sense botanical practices. An Afghan mountainous grown indica probably gets a 40F swing in temps. A sativa in Michoacan about 15F. Grapes in NAPA get a 40F temp swing up to and come harvest time.
Villa
Active Member
All I know is in the summer time when my lights out temp is higher I get less bud and less dense buds. Now that the fall is here and my lights out temps are 10-15 deg coolers my buds are much better. I don't give a shit what anyone says I grow the same plants(clones) and get better results with cooler lights out temps.
youngtrader9689
Active Member
i think its your overall temps being higher not just your night time temps what was your summer room humidity at?
youngtrader9689
Active Member
i would really like to see you do an indoor grow with 40 degree swings i know thats not what u said BUT the point is this is for indoor not everything that happens outdoor applies
youngtrader9689
Active Member
about my temps in my first post i run co2. Not gonna say my ppms because god knows it will start a presidential like debate. lol
but u see the nugs they dont lie
but u see the nugs they dont lie