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Strain for hot conditions? Sour Diesel?

  • Thread starter Thread starter BrutusKajautus
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Strain for hot conditions? Sour Diesel?

BrutusKajautus 26 Replies 3,270 Views
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BrutusKajautus

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#1
Hi farmers!

I'm reaching the end of my first grow and I leed to start my second one soon. I have a problem with ambient temps that are going to climb above 30 during the daytime no matter what I do for the whole summer. If we're (un)lucky here we might get heat waves well into August here, September should alrwady be easier.

Now I don't have an option to buy and install an industrial AC unit as I'm growing at home and the space is scarce. So I can't make the ambient temp nor the temp in my grow tent go down.

What would you suggest for a strain that can take heat well? I've been searching for a heat resistant strain, and many websites recommend Sour Diesel, but that might just be citogenesis in action. And would you suggest starting the grow so that at least the end of the flowering would not be that hot to not get weak and tasteless buds, or do you think that matters?
 
#2
maybe a strain that comes from lands where that kind of temps are almost all year round.some pure sativa maybe?

lower temps at the end of flower will preserve more terps soo yea it matters.
you could have flower over the night that would probably keep your temps around 30C and if you add co2 that would make the plant be happy in that temps.
 
#3
amneziaHaze said:
maybe a strain that comes from lands where that kind of temps are almost all year round.some pure sativa maybe?

lower temps at the end of flower will preserve more terps soo yea it matters.
you could have flower over the night that would probably keep your temps around 30C and if you add co2 that would make the plant be happy in that temps.
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Thanks! I've lost my bookmarks for heritage tree pages but maybe I can find them with a search engine and see what I can find. I've been considering that myself, and it would be great to hear from ppl who have experience with such conditions what they recommend.

I just recently heard how they handle those temps at flowring stage in Thailand, but I forgot. Need to ask the person.

Wdym by having flower over the night that would probably keep my temps around 30C? Sorry I'm having hard time understanding that sentence. It might be my brain though.
 
#4
[OLD LADY VOICE] It's not the heat it's the humidity!!! Lol

In all seriousness what's the rh like? If you can't change the temps find where you're stuck on the VPD chart and target that humidity. It's obviously going to be high so pick a strain with less dense structure to avoid mold.

You can run 70% humidity up to 35° and be fine. It's like greenhouse growing lol

The important thing is the swing to night temps, what are those like? Sounds crazy but you may have to heat the dark period.
 
#5
Grownsince95 said:
[OLD LADY VOICE] It's not the heat it's the humidity!!! Lol

In all seriousness what's the rh like? If you can't change the temps find where you're stuck on the VPD chart and target that humidity. It's obviously going to be high so pick a strain with less dense structure to avoid mold.

You can run 70% humidity up to 35° and be fine. It's like greenhouse growing lol

The important thing is the swing to night temps, what are those like? Sounds crazy but you may have to heat the dark period.
Click to expand...
Good call! I mean, I just attended to a lecture about this but forgot.

Now I need to come up with how I can maintain the humidity target in the tent with the exhust fan running. It might be that it's not a problem though, the humidity seems to creep up easily.

Night temps, that's another good point. Ig that can be like a ten degree swing, but I honestly don't know. It might be a large one. Do you have a good resource on that or do you know what kind of temp swings are acceptable and what are the dangers associated with those, except ofc RH climbing too high?

Dunno how much the RH matters during the nighttime though since only 10 per cent of the transpiration happens during the night, but there could be a limit for that.
 
#6
only strain from thailand i know is cannilope haze no idea how it will do.

what i mean is if you turn on the lamp at 9 at night after 12h it will turn off at 9 in the morning.and when the hot sun is hitting your house the tent will not be making extra heat from the lamp
 
#7
BrutusKajautus said:
Good call! I mean, I just attended to a lecture about this but forgot.

Now I need to come up with how I can maintain the humidity target in the tent with the exhust fan running. It might be that it's not a problem though, the humidity seems to creep up easily.

Night temps, that's another good point. Ig that can be like a ten degree swing, but I honestly don't know. It might be a large one. Do you have a good resource on that or do you know what kind of temp swings are acceptable and what are the dangers associated with those, except ofc RH climbing too high?

Dunno how much the RH matters during the nighttime though since only 10 per cent of the transpiration happens during the night, but there could be a limit for that.
Click to expand...
I'm talking in the sense of powdery mildew which really loves hot and dry days and cool humid nights. A lot of tent setups struggle to remove humidity at night including my own so I use a heater in the dark period to keep the swings gentle because I'm usually growing in a basement and the PM is real lol.
 
#8
Grownsince95 said:
I'm talking in the sense of powdery mildew which really loves hot and dry days and cool humid nights. A lot of tent setups struggle to remove humidity at night including my own so I use a heater in the dark period to keep the swings gentle because I'm usually growing in a basement and the PM is real lol.
Click to expand...
Ahh gotcha. I could use a dehumidifier too ig as I have one if I can find a controller with day/night settings. One local shop may have some available. Optimally I would have a VPD controller that would take over all the devices that control temp and humidity but I haven't heard of one. I wonder why.
 
#9
BrutusKajautus said:
Ahh gotcha. I could use a dehumidifier too ig as I have one if I can find a controller with day/night settings. One local shop may have some available. Optimally I would have a VPD controller that would take over all the devices that control temp and humidity but I haven't heard of one. I wonder why.
Click to expand...
AC infinity has a few
 
#10
Grownsince95 said:
AC infinity has a few
Click to expand...
Ill br damned, they do exist, and they're even available where I reside. I really really want one, have you (or others) tried one? Or maybe I should look for a thread about them or start one if there isn't one yet.
 
#11
#13
amneziaHaze said:
only strain from thailand i know is cannilope haze no idea how it will do.

what i mean is if you turn on the lamp at 9 at night after 12h it will turn off at 9 in the morning.and when the hot sun is hitting your house the tent will not be making extra heat from the lamp
Click to expand...
Oh now I got it. Thanks!

That's a good idea. I'd prefer to run the lamps during the day because they generate heat during the night and I'll be feeling that heat on top of what the sun has blazed upon us and is still lingering around. And cooler nights may be good for the plants. The days are unbearably hot in this building. But if that's what I have to do, then that's what I must do.
 
#14
BrutusKajautus said:
Oh now I got it. Thanks!

That's a good idea. I'd prefer to run the lamps during the day because they generate heat during the night and I'll be feeling that heat on top of what the sun has blazed upon us and is still lingering around. And cooler nights may be good for the plants. The days are unbearably hot in this building. But if that's what I have to do, then that's what I must do.
Click to expand...
It's better to run 30/25 than 35/25 in your situation so lights off during the heat of the day is a great idea as @amneziaHaze mentioned.
 
#15
BrutusKajautus said:
Hi farmers!

I'm reaching the end of my first grow and I leed to start my second one soon. I have a problem with ambient temps that are going to climb above 30 during the daytime no matter what I do for the whole summer. If we're (un)lucky here we might get heat waves well into August here, September should alrwady be easier.

Now I don't have an option to buy and install an industrial AC unit as I'm growing at home and the space is scarce. So I can't make the ambient temp nor the temp in my grow tent go down.

What would you suggest for a strain that can take heat well? I've been searching for a heat resistant strain, and many websites recommend Sour Diesel, but that might just be citogenesis in action. And would you suggest starting the grow so that at least the end of the flowering would not be that hot to not get weak and tasteless buds, or do you think that matters?
Click to expand...
Afghan does well in the heat.
 
#16
Grownsince95 said:
[OLD LADY VOICE] It's not the heat it's the humidity!!! Lol

In all seriousness what's the rh like? If you can't change the temps find where you're stuck on the VPD chart and target that humidity. It's obviously going to be high so pick a strain with less dense structure to avoid mold.

You can run 70% humidity up to 35° and be fine. It's like greenhouse growing lol

The important thing is the swing to night temps, what are those like? Sounds crazy but you may have to heat the dark period.
Click to expand...

That's no joke. With humidity in the 70% range and temperatures 35C/95F, even a drop into the 24C/75F range will produce condensation on the sides of your tent/grow space. This alone has the potential to bring mold and mildew issues into your grow space.
Grownsince95 said:
I'm talking in the sense of powdery mildew which really loves hot and dry days and cool humid nights. A lot of tent setups struggle to remove humidity at night including my own so I use a heater in the dark period to keep the swings gentle because I'm usually growing in a basement and the PM is real lol.
Click to expand...

WPM could be a possible problem in that environment.
TheGoldenRoad said:
Afghan does well in the heat.
Click to expand...

I was thinking along the lines of something with Thai genetics. Hot and humid is pretty normal for that area of the world.
 
#17
RoadKillSkunkHunt said:
That's no joke. With humidity in the 70% range and temperatures 35C/95F, even a drop into the 24C/75F range will produce condensation on the sides of your tent/grow space. This alone has the potential to bring mold and mildew issues into your grow space.


WPM could be a possible problem in that environment.


I was thinking along the lines of something with Thai genetics. Hot and humid is pretty normal for that area of the world.
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If we’re talking hot and humid Thai is the better choice.
 
#19
Ninjadogma said:
A South American landrace Sativa should hold up pretty well for humid heat. They've got natural defenses against mold and stuff... up to a point.
Click to expand...

That would depend. Many places in South America is mountainous which means fairly moderate year round temperatures ... However a little research on the strains in question should provide a fairly clear answer on that.
 
#20
Grownsince95 said:
It's better to run 30/25 than 35/25 in your situation so lights off during the heat of the day is a great idea as @amneziaHaze mentioned.
Click to expand...
Yeah, it might be more like 30/30 as the lamp will heat the tent up at nighttime and the ambient indoors can easily climb to 30-35 during the daytime. Or the plants' night might be even warmer than their days, since they'll be sleeping during the hottest ambient hours. I'll see.

@RoadKillSkunkHunt & @TheGoldenRoad Thanks for the heads up for Thai. I had a look at the VPD charts on different sites and they all show different optimal RH values for 30C (86F). One says 70-75 per cent, one says 75-85 per cent, one says 67-74 per cent, one says 54-60 per cent. So ig I can't yet know if it's gonna be particularly humid, but I'll surely keep Thai in mind for the case it is.

Also, thanks for the recommendations, for @Ninjadogma too, I'll dig into these genetics and lineages and see what I can find!
 
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