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Terpenes lost due to high growing heat?

de145

Member
did you go the other direction? using too much nitrogen? i can assure you the buds will come out like this.

and won't taste or smell like anything but dried grass.

Looks like an early experiment I did with landrace sativas and way too much Nitrogen, what a nightmare that was; it was like fighting triffids every day, growing into the lights constantly, hacking and chopping and bending and folding.

I've learned a lot since those days thankfully. I can now grow very smokeable and presentable landrace sativas in a shorter than 5 feet high cabinet with cfl lights. But it took a lot of experimentation to get there. Nutrient ratios are critical doing that.
 

de145

Member
nearly all the pics of un-topped plants i see posted tend to show that 'centrefold' cola sticking out the top of the plant with it's upper leaves canoeing and the tips curling up to the light. that is heat/light stress... and thats the bud that the grower will generally keep for themselves :)

VG

I can't tell if you're saying it's a bad thing or a good thing, do you mean keep because of embarrassment or because they are headstash material or...?
 

de145

Member
the soil is not 100 degrees. I grew out side in texas fro years and took soil temp a foot down and it was 70 degrees.

Also by the time it starts to flower temps max out in the 80's in the air
Excellent point!

The roots will probably always be far cooler than the canopy on a hot day outside so maybe some cooling of the tops is accomplished via the roots in a natural setting.

In a grow room or particularly a chamber or microgrow the pot is probably not a lot cooler than the tops.

There are probably a lot more factors when growing outdoors than the obvious ones we all think of right away as well.
 

VerdantGreen

Genetics Facilitator
Boutique Breeder
Mentor
ICMag Donor
Veteran
I can't tell if you're saying it's a bad thing or a good thing, do you mean keep because of embarrassment or because they are headstash material or...?

most tend to keep the biggest buds for themselves - im just saying thats the one that will have suffered the highest temps and maybe had more of its terpenes burnt off

VG
 

de145

Member
The only thing whith that is the plants can grow faster the higher the temp is. When mine hit 90 degress as long as though theres no other limiting factors they grow a lot faster than at 78 degrees.

True, the heat does affect growth speed.

I'm starting to think a possible useful trick might be to start with full on heat and lighting and in the flush period of 10 days or so move them to a cooler spot.

It's no wonder so many people have so many different experiences here; there are so many different factors that can completely change a grow. It would be very cool some day when this shit is all fully legal everywhere to get a wide diversity of growers to all grow cuttings from the same mother plant and see how it all turns out.
 

djonkoman

Active member
Veteran
I think the comparison with outdoor is flawed. I ive in a relatively cool climate(53 degrees north, seaclimate) and even here that upper limit of 29 degrees C is easily exceeded multiple times during the summer. not that often maybe, but you would probably put a plant somewhere with direct sun, and in the sun it's even warmer.
you do probably have bigger fluctuations in temp outdoors
 

Hash Zeppelin

Ski Bum Rodeo Clown
Premium user
ICMag Donor
Veteran
maybe just try adding b'cuzz bloom. It is a flower growth stimulator. It helps with just about everything. Smell, taste, yield, frost. use 2.5 to 5 ml per gallon of water.

http://www.atami.ca/america/bcuzz/index.html
poster.jpg

you want the pink bottle. dont get the knock off called green light or whatever. get this one specifically. it is the best for sure. i have done side by side trials.

Also Some sort of sugars for carbs. I like carboload, get the powder form, and mix in water your self to save money. there are many options out there for sugars. organic black Strap molasses is awesome. humbodlt honey is a really nice one too
 

RockyMountainHi

I'd rather laugh with the sinners than cry with th
Veteran
I think the comparison with outdoor is flawed. I ive in a relatively cool climate(53 degrees north, seaclimate) and even here that upper limit of 29 degrees C is easily exceeded multiple times during the summer. not that often maybe, but you would probably put a plant somewhere with direct sun, and in the sun it's even warmer.
you do probably have bigger fluctuations in temp outdoors

Who harvests in the middle of summer? :laughing:

Ya don't chop till fall - LATE fall, Ya know,,,, when it's NOT HOT
:tiphat:

Ok,,, maybe you harvest in the middle of summer, I'll wait.

My outdoor plants looked stressed in 100 deg heat outdoors. but they wern't in flower. - they recovered daily - and they were healthy.

Much like healthy people, healthy plants deal with stress better and recover stronger.

Unlike people, plants don't fatten when over fed, infact they get sick and die.
 
Last edited:

Dysnomia

Member
Any thread about terpenoids needs to have this link in them. - Russo on the entourage effect

In Cannabis, terpenoids and cannabinoids
are produced by secretory cells in the glandular trichomes. Terpenes contain repeating
units of isoprene, a 5-carbon molecule. Terpenoid naming is based on 10-carbon units:
monoterpenes contain 10 carbons, sesquiterpenes 15, diterpenes 20, etc. Monoterpenes
are lightest and evaporate most readily. Thus Cannabis extracts tend to lose myrcene,
pinene, and limonene (all monoterpenes) in proportion to beta-caryophyllene (a sesquiterpene)

Terpenoids may account for only 1%
of the weight when cannabis is tested but
10% of the weight within the trichome.
Monoterpenes evaporate more readily
than the di- and sesquiterpenes during drying,
storage, and production of extracts,
which results in a relatively higher proportion
of caryophyllene.

Regards,
Dysnomia:tiphat:
 

siddhartha

Member
Hey De145,
lots of good info here already. But in my experince UV near UV and IR are critical for terpen production. at school prof Nobel said that terpines cannot be produced without UV and near UV. HPS does not have these in there spectrum. After a ton of reasearch and with hesitation i bought a Black Dog led because of this. I did a side by side with Sour D under 1000 hps and their paltinumXl. the led had far better resin, smell and taste. dried weight was the same, just over a pound and a half each in roots organic soil, first four weeks with botanicare last 4 with AN 1 week flush with drip clean. also liquid karma through out the entire feed. Liquid karma has amino acids which are huge for aroma and taste. I plan on posting pics soon and i ordered a plant cam for this next cycle and want to do a grow journal. Hope that helps.
Sidd
 

maryjaneismyfre

Well-known member
Veteran
Interesting siddhartha.. Also, I think the ambient x radiant heat thing is important. I can for sure recall crispy buds that got too close with no smell or taste. I always had lights to supplement my HID's in indoor so that could make a difference, a few hanging 85w Tri-phosphor energy savers to be precise. Also with HID's not giving off UV ( Is this a fact ? ) having them closer wont make the plant give off more terpenes like being in a hotter climate or on a sunnier day as UV is not increasing as HID gets closer? I've gotten proper HPS tans before so I'm not too sure on the UV thing.
 

siddhartha

Member
Hey maryjane
Ya heat is a factor. When HPS is to close or to hot buds get crispy and less desirable. And supplementing HPS with florescent is a good idea. HPS does have some UV, but they shield most of it because it is really bad for your eyes. The tan thing i am not sure about. Did the tan stick for a few days or just an hour or two? the IR in a light will heat up your skin and make it red. But in class when we talked about photosynthesis, terpen production was what i paid attention to. And it was the near UV and UV that are essential for terpen production because terpenoids are a Carbon-Carbon bond. This requires more energy than what a red photon has.
Sidd
 

stasis

Registered Non-Conformist
Veteran
Look (carefully) for BROAD MITES.. They are showing up everywhere, grow fast, eat the pistils and resin glands. Depleting the buds of much of the oils that make it smell so good. Makes flowers come out crispy, instead of sticky.
 

VerdantGreen

Genetics Facilitator
Boutique Breeder
Mentor
ICMag Donor
Veteran
Hey De145,
lots of good info here already. But in my experince UV near UV and IR are critical for terpen production. at school prof Nobel said that terpines cannot be produced without UV and near UV. ......

IR i would agree helps terpene and resin production, but is also to a large extent heat and too much will burn off terpenes too.

UV - ive grown with and without using supplemental UV and i couldnt tell any great difference in the potency or aroma. sure UV may help but you can certainly grow very aromatic and tasty weed without any UV supplementation

VG
 

djonkoman

Active member
Veteran
Who harvests in the middle of summer? :laughing:

Ya don't chop till fall - LATE fall, Ya know,,,, when it's NOT HOT
:tiphat:

Ok,,, maybe you harvest in the middle of summer, I'll wait.

My outdoor plants looked stressed in 100 deg heat outdoors. but they wern't in flower. - they recovered daily - and they were healthy.

Much like healthy people, healthy plants deal with stress better and recover stronger.

Unlike people, plants don't fatten when over fed, infact they get sick and die.

then you're in luck with your climate. my usual harvestdate is late summer, start fall at last.
if I would harvest in late fall, I would only harvest mold. fall is wet and high humidity here, and especially later in fall when it gets colder humidity increases more and resistance of the plants is probably less too.
best harvest time is begin to mid september here, but october is very well possible too if it's a good year and the strain is moldresistant enough.
but any later as october isn't feasable
and there are also people getting good results with autoflowers harvested in midsummer
 

Hash Zeppelin

Ski Bum Rodeo Clown
Premium user
ICMag Donor
Veteran
Hey De145,
lots of good info here already. But in my experince UV near UV and IR are critical for terpen production. at school prof Nobel said that terpines cannot be produced without UV and near UV. HPS does not have these in there spectrum. After a ton of reasearch and with hesitation i bought a Black Dog led because of this. I did a side by side with Sour D under 1000 hps and their paltinumXl. the led had far better resin, smell and taste.
Sidd

Grown under a 1.5 year old hps bulb in dwc.





 

THC123

Active member
Veteran
Just increase ventilation so that the temps dont go higher then 24-25 gedrees and you ll be fine under hps

with my first indoor grows i had the same problem, its the heat of the hps toasting your buds

outdoors still takes the cake imo in smells and aromas
 
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