Promix HP is peat + perlite, IIRC. Mix discussed is peat +vermiculite. Vermiculite is not same as perlite but specifically chosen.
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Bugbee may have moved away from vermiculite. It’s not sustainable and always considered a PACM (presumed asbestos containing material) as it’s mined in the same mines and you have no idea what source is in your bag. He also stated in old videos that verm contributed Si, but it doesn’t per his latest offerings.
I still add verm to Promix HP to get it to 50% peat, for the tradition only!
Example:
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I wonder if this toxicity is based on application rate? Bugbee did study on application rates and seemed very interesting on how the plants can store and shuffle the mobile nutrients. The constant topping off of nutrients might not benefit the plant. I think when the concentration of big 3 drops then it can go after the more passive Ca and magnesium if concentration is low enough? Yo-Yo effects in a way? VPD plays such an important role in nutrient utilization too. We know calcium issues arise because of too high of VPD (dry) conditions dictate high water consumption and concentration rising too high and only most mobile nutes get absorbed and passives are then deficient. Yes always playing with moving targets.
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I mean per that study, 30% is high end for ammoniacal, while PLS is 40%. BUT it’s on coco which is BS. Hint is to look at Jack’s Tap.
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so…not a fact then. whereas specifically mentioned here:
and with the reason as to why. No mentions of asbestos or mines or little green aliens with 3 heads.
We’re still discussing facts, yea? I mean I’m not building a church for the man, but I’d like to keep on topic.
I do not think comparing apples and oranges will do.
Jeez you’re combative, but also sorta correct depending on if you want to get me! I was thinking of this post right here:
Where he dropped verm from 50% to 13% (i.e. “moved away from”). But I get it!
P.S. Amongst other things I’m a licensed asbestos project designer. (Hit me up if you need a design on the cheap, $70/hour). The factoid about asbestos is true for sure, not that it stops me from using it, and I still go for that version 1 blend @ 50% for that sweet CEC as you do.
…And since he’s using 12% rice hulls for Si, yet Wollastonite is where we now get our Si, I drop the rice hulls… don’t need them. They are just filler that that point. So, I substitute some perlite, I use 12% perlite. It turns out that Promix’s ready-made HP blend ends up being around 12% perlite when mixed with vermiculite. That’s alarmingly exactly what I need. I can just add verm, wollastonite and gyp. It already has the wetting agent, the lime, and also delicious mycorrhiza, it’s sterile and consistent, it’s so widely used it’s FRESH, it’s cheap too from my local Griffens. You should consider it.
In the end, the nature of peat as a media is the same between the two, and I mention promix because it’s the best, most-similar mix we have to point at, and they just so happen to offer tons of interesting articles, and learning modules on these topics.
P.S. https://documents.deq.utah.gov/air-quality/compliance/atlas/asbestos/DAQ-2021-004667.pdf
I’ve seen this is other states… I bet they drop verm completely at some point. It’s not that “asbestos bad” it’s that vermiculite dust ends up rendering public facilities as asbestos contaiminated, and abatement is expensive. It’s purely administrative.
A: USU collaborates with local Utah high-THC genetic growers.
you might be reading non existent subtext…
I’m comparing apples to apples. Statement like “may have changed” do not cut it. The video I refer to for my current run I posted above. 50/50 peat/vermiculite + lime is specifically mentioned. And the reasons for it explained in a manner that I understood them.
That’s it. No one out to “get” anyone. this is the internet. I could be 12 mad ferrets in a trenchcoat. who cares.
I am using the method delineated in the video now. I am liking what I am seeing. I am going to run it to completion. If I like the result, I will stick with it. If I don’t, I will change it.
congrats on the hourly rate. it’s very nice.
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Just bumping before 2022 is over. If you’ve followed along, just know that USU has updated a few things since that “maximizing cannabis yields” video was posted.
PLS is Peter’s most common fert for peat-based (promix) DTW greenhouse growers. It’s 40% ammoniacal, which is done to combat the rise in peat media pH over 100+ days of use in annual season settings. It’s a system that greenhouses everywhere use, including the ones I work in. USU uses it because it’s ubiquitous, simple to use, can almost be mixed by eye, and more specifically USU needs a datum plane, a standard feed, to study OTHER things like spectral effects of different LEDs. Notice they aren’t studying THC/terpene/secondary metabolite production as a function of nutrition, and never will without Fed licensing.
People find his Maximizing video and may assume these methods were the result of years of research into best methods for cannabis production, or at least “what works in a research setting”. Well… All we know is that these methods are what the USU program uses to standardize X, so that they can go study Y. The feed and mix is the same stuff we use for leafy veggies, but not for tomatoes, strawberries, or other fruiting crops… we have specific feeds for those and indeed might phase in things at different stages of life.
Lastly, Dr. Bruce offers a TON of between-the-lines info in his recent youtube offering on Phosphorus for example where he shares that some cultivars need way more than PLS. Which ones?!
Happy 2023 all! PM me if you want to chat on the topics more. I know I sucked up all the air from this thread.
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Many people think that more is better when supplying nutrients and that it is better
to have excess nutrients in the solution than levels that are only adequate. This is not true
and this thinking leads to dangerous imbalances in nutrient uptake. For example,
potassium is absorbed rapidly from nutrient solutions. If potassium is supplied at excess
levels its uptake inhibits the uptake of calcium and induces calcium and magnesium
deficiencies. Keeping potassium at appropriately low levels in the root zone significantly
improves calcium uptake and helps to prevent blossom end rot, a common calcium
deficiency disorder in tomato fruits.
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Would a very high cbd skunk be legal if the thc was say less than 0.3%. The mechanism for high CBD and High THC is there only THC is still schedule 1. A high CBD plant can react positively based on selection and nutrient requirements. I would say that the nutrient profile for a high CBD would share something in common with a high THC skunk? Why can’t they look at terpene metabolite production?
Happy New Year!
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@Cactus Dr. Bugbee mentioned to me that high and low THC cannabis is dissimilar by only two genes. I’d imagine the mechanisms are the same right? Remember that “highest yeild” never equates to “highest cannabinoid content” … too many papers and common knowlege showing that various stressors improve the plants emphasis on seed protection (resin glands, thrichomes, chemicals to keep bugs away, density of said trichomes to shade from UV. Feeding low N (less than 150 for sure) and phasing out N in flower whilke keeping other elements high is a must for potent herb IMO, and it kills yield.
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@LD50 I wonder if an approach to the situation you are describing has another option. You mentioned lower levels of THC due to larger flower growth? The genes of how the cannabiniods are inherited; Bt x Bt = high THC, BtxBd = Moderate THC and CBD Bd x Bd = High CBD. Might be a Bo modifier not sure if they ever found out how that works. 1:2:1 setup in Mendel terms.
I wonder if bigger plants produce larger tri-chomes? If you want want to increase the tri-chome size can you just veg the same plant longer and get a bigger plant with larger tri-chomes? Just some random thoughts.
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Loving the thoughts this provokes!
So to touch the canopy size vs cannabinoid content:
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https://www.frontiersin.org/articles/10.3389/fpls.2021.764103/full
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Not a favorite study, a vague hit-piece on P again, quoting a 200 mg/ml solution as bad (no shit) and 30 mg/ml as a proper limit (in veg) and no mention of P in flower
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Table 6… c’mon guys show us all of the data, even the outliers. I want to grow outliers!
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No one is phasing nutrient solutions over time, over a run, like nature does. The one big lie is that we should feed a constant nutrient solution over the run. Funded research gets done. Who’s funding??
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School of environmental sciences involved = REDUCE P = genetic selections with low P chosen to show results is a natural motivation.
Anyways, then look at the notes:
- While the cannabinoid concentrations in the floral tissues in our study did not respond to nutrient solution NPK concentrations, other studies indicate that plant mineral nutrition can affect production of secondary metabolites in cannabis (Caplan et al., 2017a; Saloner and Bernstein, 2021). There appears to be an inverse relationship between cannabis yield and potency, with cannabinoid concentrations decreasing as plant inflorescence yield increases. Inflorescence from plants supplied with 160 mg L–1N had approximately 30 and 20% lower concentrations of THCA and CBDA than plants supplied with 30 mg L–1N (Saloner and Bernstein, 2021). However, while nutrient stress and deficiency may enhance inflorescence cannabinoid content, this method is not ideal for optimising overall plant productivity as plants supplied with 160 mg L–1 N yielded twice that of those supplied with 30 mg L–1N.
So in the end, you can double yield and increase total cannabinoid weight with a higher N supply, and economically speaking this looks good - you’d divide the cannabinoid weight harvested by the energy used to get it, and come up with a $ value. You’d get more cannabinoid per watt. But if you’re a hobby shop grower, you might get bored of chasing data efficiencies and look for the real summit, effect-per-unit-hit.
Look at this one too:
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https://www.frontiersin.org/articles/10.3389/fpls.2022.830224/full
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Considering effect of N availability in the plant tissue: We have recently demonstrated that an optimal N nutrition, and high concentration of N in the plant, do not correlate with high secondary metabolism in cannabis (Saloner and Bernstein, 2021). Rather, we claimed, that the main factor governing the decrease in cannabinoid and terpenoid production is the tissue N content, which increase gradually with the increase in N supply (from 30 to 320 mg L–1) (Saloner and Bernstein, 2021). This suggestion, supported by results for numerous other plants (Bryant et al., 1983; Coley et al., 1985; Fritz et al., 2006; Palumbo et al., 2007; Massad et al., 2012; Albornoz, 2016), supports the carbon-nutrient balance hypothesis which states that under low N content production of N-rich primary metabolites and hence growth are restricted, and plant metabolism and energy expenditure shifts from creating N-containing metabolites to the production of metabolites that do not contain N
You know, like THC:
Edit, and CBG
- … indeed confirm that the production of secondary metabolites in the cannabis inflorescence is highest under low N concentration in the inflorescence and in the plant, and decreases with the increase in inflorescence (and plant) N concentration (Figure 7A).
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This is pretty much what I think about Bugsby’s work on the nutrient side of things. Lighting and limiting factors I agree 
Both THC and CBD use the same precursor, CBG, so at least the first portion is the same.
I have heard this is the case by some hash makers.
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I wonder if something like this might work?
- Set your veg formula to the 120-60-120
- Measure EC say 1.2.
- 24 hrs later measure water consumption &
EC. EC comes back 1.0 lower by 0.2 then
Solution is too weak bump it up to EC 1.4 - Check again water consumption is still same
EC still same = equilibrium
I believe you have to practice with this to get a feel for it jmo. Playing with the ratios and dialing Bug method is safe starting point for the new grower. I think these conversations aren’t teaching anything new @LD50 but good for growers new to growing in hydroponics.
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Consider PLS at 150 N… The main reasons:
- Not enough P (33 mg/ml)
- It’s 40% ammoniacal, way too much
- Not enough Fe.
This is PLS vs. 321 @ 150 N
I only run 150N in veg, and in flower I run 140, 120, 80, 50 over the course of the weeks. To do that I need to run multiple inputs and mix them in parts. PLS doesn’t offer much here, because when you lower the concentration to seek a lower N target, the other already-low macros and micros scale out. I like to use Jack’s Hydro as a base and scale the CalNit and epsom up and down, same with added K and MKP. I also use a hint of jack’s citrus to bring in some ammoniacal, but not more than 20% total and I pull that back to all Nitrate (just very little of it) by harvest.
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Do you nano or reverse osmosis your water? Or do you have a water report for your data and go from there? @LD50
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Municipal tap water from a really good (aka well funded) water district. The charts you see there have data corrected for what’s in my particular tap water.
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