Quest for mold-resistant strains, Hawaii outdoor greenhouse grow

[cbdhemp808]

Greetings Growmies,

Super Lemon Haze has come back on my radar screen, which is one of the strains I looked at when researching bud rot resistance and terpinolene dominance. This is thanks to @JenniM having posted photos of her mystery plant in her thread HERE, and for @StarkRaven who thought it might be related to SLH.

In my research, SLH was at the bottom of my CHART for hypothetical bud rot resistance, and not super high in total terpenes (which correlates to resin production). Nonetheless, it had high terpinolene and high pine terps.

What I really like is SLH's structure... it's one of those "all bud" type plants. This is something that I'm just now learning about, and definitely want to try growing, and possibly breeding someday. I don't know how well they would work outdoors here in Hawaii, but there are also some Thai genetics that look like this.

Here are some other "all bud" type plants. Note that this structure isn't necessarily only common to sativas... see Wonder Pie below.

Panama A5 Haze (ACE Seeds). Tall sativa, high in terpinolene and ocimene.

photo: Alchimia

Killer A5 Haze (ACE Seeds). 3 sativa phenos, 1 indica pheno.

photo: Mandala Seeds

Wonder Pie (Green House Seeds). Tall 50/50 hybrid -or- indica dominant. Typical indica terpene profile. Unknown if there's a sativa pheno. There's African, Mexican, and Thai sativa in its lineage.

photo: Reddit, Cannabiscultivation group, user ThanksFederal4285

 

[StarkRaven]

You got one fat main cola man! You could knock someone out with that be careful when you harvest her.

 

[cbdhemp808]

You got one fat main cola man! You could knock someone out with that be careful when you harvest her.

Just informational. I post lots of things, including photos of plants that I haven't grown (yet).

 

[StarkRaven]

I'll definitely stick around your the first Hawaii grower I met! Glad to of met you best part of this website is meeting people from all over the world and learning about their techniques and methods it's awesome that people here are so willing to help out when able.

 

[JenniM]

Hey Growmies,

I've had a big breakthrough tonight, actually a couple.

First, I have finally figured out terpene evaporation temperatures, which are very difficult to find online. If you try to search for this, what comes up are boiling points. And the boiling point information is sometimes not accurate. Evaporation temperatures are important to the process of drying and curing. In addition, terpene evaporation temperatures are interesting with respect to the research I've been doing on the role of terpenes in bud rot and leaf mold resistance.

The key to understanding (and finding info on) terpene evaporation temperatures is vapor pressure. I'm still in the process of fully understanding this; however, vapor pressure is a measurement of the volatility, which is the "tendency of a substance to evaporate at normal temperatures."

The below chart is from an research paper I came across, titled Vapor Pressure, Vaping, and Corrections to Misconceptions Related to Medical Cannabis’ Active Pharmaceutical Ingredients’ Physical Properties and Compositions, Aharon M. Eyal, et al. 2022 ...

Here we can see that the monoterpenes are by far the most volatile, and start evaporating at 68°F (20 C). At 120°F (50 C) and above, they are really taking off. The primary monoterpenes in cannabis are pinene, myrcene, limonene, terpinolene, terpinene, ocimene, and terpineol (a monoterpenoid). The sesquiterpenes are much less volatile, and start evaporating at 212°F (100 C). The primary sesquiterpenes are: beta-caryophyllene, alpha-humulene, and bisabolol (a sesquiterpenoid).

In terms of bud rot resistance, and potentially leaf mold resistance as well, clearly the monoterpenes are the only ones to consider. The higher the daytime temperatures, above 68°F, the more they will off-gas. A more complete list of vapor pressures for the monoterpenes is shown in the below, Table 3.

Below is Table 3 from Aharon M. Eyal, et al., showing both boiling points and vapor pressure at sea level (1 atmosphere or 760 mm Hg) of various terpenes...

Now we can see which of the monoterpenes is the most volatile at 68°F (20 C), looking at the vapor pressure from the above chart (Torr -or- mm Hg), with caryophyllene and humulene listed at the end for comparison...

alpha-Pinene........ 3.570
beta-Pinene......... 2.180
beta-Myrcene........ 1.690
Limonene............ 1.130
Terpinolene......... 0.799
beta-Caryophyllene.. 0.021
alpha-Humulene...... 0.010

Next, I'll fill out this monoterpene volatility chart by adding the other primary monoterpenes, and increasing the temperature to 77°F (these number are from other sources, not the above research paper)...

alpha-Pinene........ 3.489
beta-Pinene......... 2.399
beta-Myrcene........ 2.090
alpha-Ocimene....... 1.970
alpha-Terpinene..... 1.665
beta-Ocimene........ 1.559
Limonene............ 1.550
Terpinolene......... 1.126

From this we can see pinene and myrcene are the most prominent off-gassing terpenes at a normal daytime temperature of 77°F. In my research on pine and non-pine terpenes, I found correlation with sativa/indica distinction, and also with bud rot and leaf mold resistance. Now we can ask the questions, which are more volatile, pine or non-pine terpenes? Since myrcene and limonene are the only two prominent non-pine terpenes*, it's obvious that pine terpenes are the most volatile. (*Linalool clocks in a just 0.170, so it's not very volatile. bisabolol is a sesquiterpene, so barely registers any volatility at 77°F. Same for nerolidol.)

This is a cool discovery, because I theorized that terpinolene was the active terpene for bud rot resistance, in terpinolene dominant phenos. I also theorized that pinene/myrcene dominance was responsible for leaf mold resistance. When terpinolene is dominant, along with high levels of other pine terpenes, the overall effect is a lot of off-gassing of pine terpenes, and this supports my theory of bud rot resistance.

It's important to note that total off-gassing is a function of both the volatility of the terpenes present, and the percent by weight of each terpene present. If you've got both high volatility, and high percent, good things are going to happen.

~~~~~​

Second, I have finally also figured out the boiling points of terpenes. If you look these up online, there's wild disagreement depending on the source. I think the variation is due to the fact that a lot of chemical databases will show boiling point temperatures at various atmospheric pressures other than 1 atmosphere (which is 760 mm Hg), i.e. the pressure at sea level.

This is my own table, based on data from two different chemical databases that were in agreement, except as noted with "(2)", and at 1 atmosphere...

Here we can see the boiling points as not a fixed number, but as a range, with the first column being the lowest recorded boiling point. The chart is ordered with the highest boiling point first (beta-caryophyllene). The far right column, "type," is the type of terpene: S=sesquiterpene, M=monoterpene, Mn=monoterpenoid.

This chart is important for understanding vape temperatures; i.e. as long as your vaporizer is operating at 368.6°F or above, you'll be getting all the main monoterpenes. You can't vape beta-caryophyllene, because the combustion temperature of cannabis is 451°F. Terpineol at 423-424°F is fairly close to the combustion temperature.

This is the stuff research paper! Knowledge is power

 

[JenniM]

This is the stuff research paper! Knowledge is power

lol spelling, this is the stuff I love! Learning and gaining valuable knowledge. Great paper

 

[cbdhemp808]

lol spelling, this is the stuff I love! Learning and gaining valuable knowledge. Great paper

I love doing the research and writing about it. The world of cannabis is huge... it's like a tree with a whole lot of branches, and out on the end of the branches there's just lots of stuff to do research on, and it dips into various sciences. Add to this all the information on the 'net, and if you know how to dig for it, voila... you can come up with the answers.

I've got a lot of "research paper" type writing on the forum here.

Here's one you might like to check out, regarding the origins of cannabis...

It starts HERE. Continues HERE, HERE (and scroll). HERE. HERE. HERE.
But wait, there's more... HERE , HERE, and HERE. <== The End

Wow, I had forgotten how long that one was! It's got to be the longest on a single subject. I did lots of research on terpenes and bud rot resistance in this thread, but it's not a "story" like the origins of cannabis one.

Teaser...

Humulus japonicus

 

[Fenderbender]

Greetings Growmies,

Super Lemon Haze has come back on my radar screen, which is one of the strains I looked at when researching bud rot resistance and terpinolene dominance. This is thanks to @JenniM having posted photos of her mystery plant in her thread HERE, and for @StarkRaven who thought it might be related to SLH.

In my research, SLH was at the bottom of my CHART for hypothetical bud rot resistance, and not super high in total terpenes (which correlates to resin production). Nonetheless, it had high terpinolene and high pine terps.

What I really like is SLH's structure... it's one of those "all bud" type plants. This is something that I'm just now learning about, and definitely want to try growing, and possibly breeding someday. I don't know how well they would work outdoors here in Hawaii, but there are also some Thai genetics that look like this.

Here are some other "all bud" type plants. Note that this structure isn't necessarily only common to sativas... see Wonder Pie below.

Panama A5 Haze (ACE Seeds). Tall sativa, high in terpinolene and ocimene.

photo: Alchimia

Killer A5 Haze (ACE Seeds). 3 sativa phenos, 1 indica pheno.

photo: Mandala Seeds

Wonder Pie (Green House Seeds). Tall 50/50 hybrid -or- indica dominant. Typical indica terpene profile. Unknown if there's a sativa pheno. There's African, Mexican, and Thai sativa in its lineage.

photo: Reddit, Cannabiscultivation group, user ThanksFederal4285

But isn't that the structure you want to avoid for your location? As all bud.. well stagnant air and moisture.
Tropical Sativa with buds spaced over longer internodes probably less prone?

 

[RedskinnedRhino]

Greetings Growmies,

Regarding mold-resistant strains... I've done a bunch of research over the past few days, looking for available seed for strains with the following qualities:

high levels of myrcene (or already known to have high mold-resistance)
have blueberry or white widow genetics (both have high myrcene)
heavy resin production (also implies strong odor)
sweet, fruity odor
not a long flowering time
good yield
euphoric/happy effect
high THC

'Forbidden Fruit' checked all of those boxes, when I grew it.
Had no mold, flowered pretty quickly, large harvest from a small plant, smelled of rotten fruit, excellent daytime buzz that gave me energy instead of taking it away.
One of the few strains that I plan to grow again.
Just my 2c.

 

[cbdhemp808]

But isn't that the structure you want to avoid for your location? As all bud.. well stagnant air and moisture.
Tropical Sativa with buds spaced over longer internodes probably less prone?

Good question. Hmm, I don't see it that way, because take a look at this plant (first photo). There's not a lot of leaves to block airflow and reduce solar heat on the buds. There's great air flow. I mean, look at it this way... a "normal" plant is going to have lots of big buds, so there's no difference in that regard. What's different is the arrangement of the big buds. This is a sativa, with bud rot resistant pine terpenes. There's no foxtailing. To me, this is a near perfect, symmetrical arrangement of well-spaced buds, both branch-to-branch and along each branch.

The second photo below is Mango Thai, a tropical sativa, with a similar structure, but with lots of fan leaves, and what looks like foxtailing. The 3rd photo is my #9 CBD pheno, which produced fairly big, dense colas that were completely free of bud rot. The next photo is Oregon CBD's Sour Hawaiian Haze, a type 3 CBD plant. The next photo is Skywalker Haze, another strain with big colas, recommended by Dutch Passion for growing in the tropics. The last photo is Amnesia Haze, also recommend for growing in the tropics, with big colas and a huge central cola.

If growers in Hawaii have tried growing "all bud" type plants, and have failed due to bud rot, perhaps they were trying strains/phenos that weren't bud rot resistant. For example, there are some Haze strains with indica phenos, and those phenos are typically absent of the pine terpenes associated with bud rot resistance.

If there's lots of resin, and pine terps, I think it would work out. These large-cola, big central cola sativas are recommended for the tropics, but there's a caveat—beware of the indica phenos.

photo: @JenniM

Mango Thai #2 (The Real Seed Company). Sativa landrace.

My Cherry Blossom CBD #9 pheno, harvested in May '24. 50/50 hybrid.

Sour Hawaiian Haze (Oregon CBD). Sativa dominant type III CBD plant. Myrcene dominant, followed by terpinolene.

photo: Fern Valley Farms

Skywalker Haze (Dutch Passion). Sativa dominant. Some phenos have high terpinolene and ocimene.

photo: Greybeard Seeds

Amnesia Haze (Soma Seeds). Both indica and sativa phenotypes. At least one sativa pheno has terpinolene dominant. (I posted some more photos of Amnesia Haze... see below "Some more examples of Amnesia Haze...")

photo: @radrichie61 , Sept. 2023, thread.

Thank you @Fenderbender, that was a fun one!

 

[cbdhemp808]

'Forbidden Fruit' checked all of those boxes, when I grew it.
Had no mold, flowered pretty quickly, large harvest from a small plant, smelled of rotten fruit, excellent daytime buzz that gave me energy instead of taking it away.
One of the few strains that I plan to grow again.
Just my 2c.

Thanks. I've since moved on from myrcene to identify terpinolene and the other pine terpenes as the ones associated with strong bud rot resistance. That said, although Forbidden Fruit phenos have myrcene dominant, some phenos apparently also have significant amounts of terpinolene and other pine terps. I can understand that, because it has Durban Poison, Granddaddy Purple, and Skunk #1 in its lineage. It's said to be an indica dominant strain, but some say the effects lean toward sativa. It may actually be both bud rot and leaf mold resistant, which would be really great in my case. I see Humboldt CSI has Forbidden Fruit S1 and some nice crosses in stock. The Granddaddy Purple cross is interesting, because it may impart indica effects, while retaining significant terpinolene and other pine terps.

 

[cbdhemp808]

Some more examples of Amnesia Haze, showing christmas tree shape and big central cola, similar to the ones shown above.

These are from @EDzMEDz420 in 2016

 

[Fenderbender]

Jack Herer? Mostly Terpinolene, Caryophyllene & Pinene

I kinda would also have thought that more wild foxtaily strains would be more resistant instead of big dense nugs... but yeah maybe not it's a lot of plant material next to each other where a big fat bud can get a resin coating that's protected from the elements a bit.

I'm gonna give this a try next year outdoor, see if a plant with your terp profile can resist more rot.
But yeah here it's not only high humidity but the temperature & Sun exposure skyrockets down in the midst of flowering.

 

[cbdhemp808]

Jack Herer? Mostly Terpinolene, Caryophyllene & Pinene

I kinda would also have thought that more wild foxtaily strains would be more resistant instead of big dense nugs... but yeah maybe not it's a lot of plant material next to each other where a big fat bud can get a resin coating that's protected from the elements a bit.

Yes, protected specifically from fungus and mold spores coming in on the air currents. I fully believe that the pine terps, and possibly also myrcene is good, actually kill the spores and/or prohibit them from growing, due to off-gassing directly from the trichome caps.

I'm gonna give this a try next year outdoor, see if a plant with your terp profile can resist more rot.
But yeah here it's not only high humidity but the temperature & Sun exposure skyrockets down in the midst of flowering.

Jack Herer was high on my original list, with high total terpenes, high terpinolene, and high ratio of pine to non-pine terps. I think I decided against because there are phenos to hunt through.

Here's a terpene volatility chart at 77°F. So, pinene is the most volatile and off-gasses the most readily. Followed by myrcene. And then the other pine terps, ocimene and terpinene. Then limonene. And lastly, terpinolene. But the thing about terpinolene is that it's usually sort of the "leader of the pine terps"... when terpinolene is dominant, the other pine terpenes are typically also present in significant amounts. In 50/50 strains, we see pine and non-pine terps more in balanced amounts ("HYB" in the chart above, where "H" is closer to 1.00).

alpha-Pinene........ 3.489
beta-Pinene......... 2.399
beta-Myrcene........ 2.090
alpha-Ocimene....... 1.970
alpha-Terpinene..... 1.665
beta-Ocimene........ 1.559
Limonene............ 1.550
Terpinolene......... 1.126

 

[Melville Hobbes]

I came across something saying Carnival is high in terpinolene. Did you ever come across a terp profile for it?

 

[cbdhemp808]

I came across something saying Carnival is high in terpinolene. Did you ever come across a terp profile for it?

Strain info online points to terpinolene dominant (for at least 1 pheno), but I can't find any terp profile for it.

 

[Fenderbender]

Yeah Melville needs a mold resistant strain too!
And me! As harvesting late September sucks when they need a couple more weeks.

I'm thinking is pheno hunting not what we should be doing then? as finding beans to chuck that give you the desired properties each time is nigh impossible.. Need to find the pheno that does it at your place and then clone the crap out of it's mother.

I recently found La Chanvriere Purpurea Stella.. Not that it's especially mould resistant could be don't know.. but it's supposed to be harvestable mid Sep.. Which is how I hack outdoor growing, like Channel+ bulks up really fast and if I have to cut it down late September it's able to deliver a kilo of pretty nice weed.

"Outdoor line worked for a decade to ensure harvest for outdoor growers in difficult aera’s, like The Netherlands, Belgium, Luxemburg.
Full proof early purple strain with rose, lavander and spicy taste, a candy for eyes and mouth.
Harvest before 15 sept.
Genetics= Oregon Rocket, Kurple Fantasy, Fat Purple, Purple Mayhem."

But it only comes in regulars.. but outdoor that's doable space enough and cull the males.
La chanvriere seems to be a large hemp seed manufacturer in Northern France but there's no info on this Purpurea except for the seeds at Organic Earth in Maastricht. So maybe a low key side project?
But I'm tempted to try.
It's a purple strain those usually have a helping of pine terps.

 

[PurpleGunRack]

I highly recommend Platinum crosses for mold resistant powerful strains, expensive seeds but you get a big bang for your buck
Platinum Jelly is my favorite strain of all time (so far)

Frisian Dew is also great for mold resistance, but not the hardest hitting strain. Interesting terp profile ranging from tart grapefruit to sweet strawberry bubblegum.

Pretty much any ''pure'' sativa (ACE's Panama and Malawi are stellar) will do very well because of the fluffy buds, but it might be necessary to do some light deprivation to initiate flowering at the right time.

Sugar Black Rose is a very nice strain, haven't grown enough plants / different seasons to know much about its mold resistance. I would definitely top it multiple times, it gets pretty fat.

All Sensi Seeds strains I've tried have been a total mold show, crumbling away next to Platinum crosses in the same grow with fatter buds and no mold.

 

[cbdhemp808]

Yeah Melville needs a mold resistant strain too!
And me! As harvesting late September sucks when they need a couple more weeks.

I'm thinking is pheno hunting not what we should be doing then? as finding beans to chuck that give you the desired properties each time is nigh impossible.. Need to find the pheno that does it at your place and then clone the crap out of it's mother.

Sure, you can pheno hunt. I'm just saying that if you want to minimize the hunting, then go for a strain that has known phenos, and one that you can find terpene profiles for those phenos. That's what I'm doing. It can take some Sherlock Holmes work. Another factor is finding a good source for a good seed line.

I recently found La Chanvriere Purpurea Stella.. Not that it's especially mould resistant could be don't know.. but it's supposed to be harvestable mid Sep.. Which is how I hack outdoor growing, like Channel+ bulks up really fast and if I have to cut it down late September it's able to deliver a kilo of pretty nice weed.

"Outdoor line worked for a decade to ensure harvest for outdoor growers in difficult aera’s, like The Netherlands, Belgium, Luxemburg.
Full proof early purple strain with rose, lavander and spicy taste, a candy for eyes and mouth.
Harvest before 15 sept.
Genetics= Oregon Rocket, Kurple Fantasy, Fat Purple, Purple Mayhem."

But it only comes in regulars.. but outdoor that's doable space enough and cull the males.
La chanvriere seems to be a large hemp seed manufacturer in Northern France but there's no info on this Purpurea except for the seeds at Organic Earth in Maastricht. So maybe a low key side project?
But I'm tempted to try.
It's a purple strain those usually have a helping of pine terps.

I would go for genetics that are tried and true, where there are known phenos. All seed lines will throw at least 2 phenos. Some will throw 5-7 known phenos. Sometimes there will be phenos beyond the known ones. Often there are both indica and sativa phenos. The more stable a seed line is, the more these things can be known. That's where breeder skill and experience comes in. Very important.

For the strains I'm focusing on, I have determined the known phenos, and have found terpene profiles for them. And, I've found good sources for the seed. Unfortunately, by the time I'm ready to buy the seed, the landscape may have changed.

I'm also shooting for maximum total terpenes, implying very high resin production. This is because my outdoor environment here in Hawaii is an extreme situation of fungus and mold. I'm aiming high.

Here's my current short list for THC plants. There are some others that I am considering as well, including Super Lemon Haze. There are some other good ones in the chart I posted above. (If you want to grow type III CBDs, or 1:1, let me know.)

• Chernobyl, Slymer pheno, S1 (sativa dominant)
• Agent Orange (50/50, sativa leaning)
• Grand Daddy Purple (indica dominant)
• Atomic Northern Lights (indica dominant)

All are high resin producers. Chernobyl and Agent Orange are terpinolene dominant. Grand Daddy Purple has significant amounts of terpinolene—rare for an indica dominant plant. Even more rare in this regard is Atomic Northern Lights, which is terpinolene dominant.

So, this is my approach. As long as you can find a terpene profile (lab test results) for the pheno(s) of the seed line you're interested in, you can have a look and determine the ratio of pine to non-pine terpenes, and usually if there are significant pine terps, you'll also see terpinolene. That's what I've seen in my research.

There are lots of sativas that have terpinolene dominant. But there are also lots of seed lines claiming to be X% sativa, but in reality, the seed line will throw both sativa and indica phenos. Some throw mostly sativa phenos, and perhaps one indica pheno. For some indica strains, you may see the opposite.

 

[cbdhemp808]

I highly recommend Platinum crosses for mold resistant powerful strains, expensive seeds but you get a big bang for your buck
Platinum Jelly is my favorite strain of all time (so far)

Thanks for the tip. Platinum hadn't come up on my radar because I couldn't find any terpene profiles for it. That could be because terpinolene isn't dominant, and that's what I was focusing on.

Platinum Jelly is a 50/50 hybrid.

This is the best terpene profile I could find for Platinum Jelly, showing significant ocimene and pinene. There's only a trace amount of terpinolene. So this is very interesting... a case where there are significant pine terpenes, but not terpinolene. First really I've seen of this.

There appear to be several phenos of Platinum Jelly, with at least one having terpinolene dominant. I just can't find other terpene profiles, nor any information about the known phenotypes. Some phenos could have either indica or sativa effects, while one or more may have a balanced combination.

Pretty much any ''pure'' sativa (ACE's Panama and Malawi are stellar) will do very well because of the fluffy buds, but it might be necessary to do some light deprivation to initiate flowering at the right time.

Yes, they are well known to often have terpinolene dominant. That's my marker for bud rot resistance, in addition to high resin production. But I don't want a super long flowering time which is typical of a lot of these landrace sativas. I tried ACE's Green Mountain Grape sativa and it fell to bud rot. (Lately I've been eyeing Panama A5 Haze, but alas, very long flowering time.)

I don't have to worry about initiating flowering here in Hawaii. It happens year round, due to our consistently long night length. I have to worry about the opposite, so I use night interruption lighting in my veg house.

Sugar Black Rose is a very nice strain, haven't grown enough plants / different seasons to know much about its mold resistance. I would definitely top it multiple times, it gets pretty fat.

Definitely, and it's at the top of my chart above. I'm not going for that one because the sativa pheno is hidden among 3 indica phenos. But someday maybe... the resin production is super high, as are the pine terps. It could be ideal.

All Sensi Seeds strains I've tried have been a total mold show, crumbling away next to Platinum crosses in the same grow with fatter buds and no mold.

It boils down to the terpene profiles and the resin production. That's my understanding. In addition, high quality breeding for stable, reliable seed lines.