Also, what’s a good starting point for N for a flower formula? If running say around 160 No3, is 100N a good starting point for flower or, is that going to be dictated by tissue samples? Also if dropping CaNo3 in flower, where does the Ca come from then? Ca Acetate? If I run close to a 1:1 N:Ca ratio, should I be dropping the Ca along with the N in flower? Keeping them close to a 1:1? Sorry for all the questions. 
I was wondering what some of you nutrient pros thought about this new offering I saw on IG.
I don’t know much about the topic of nutrient analysis but I am becoming very interested in the things you all are talking about.
I love the idea of using tissue analysis and other forms of analysis to guide the nutrient program. Things have certainly come a long way from 10 years ago when I was last growing and it was basically all guessing.
Here’s a couple interesting quotes from the caption.
“…those who have used it have told me the taste of the finished product is noticeably improved compared to what they got before with other popular nutrient products. Doesn’t hurt that it also costs literally half of what most all other competing products out there do per gallon made, since we don’t just re-bag calcium nitrate and mark it up 500X like almost every single one of them does.”
" I 100% guarantee you will see our competitors (the smarter ones at least) come out with a “bloom 2” or “finisher” recipe soon to add to their lineup that also includes calcium chloride (or some other form of calcium without nitrogen) and reduces nitrogen for either all of flower or at least after week 3."
@Tech1145 The cheapest way to approach nutrition at a medium to large scale will always be to mix your own nutrients. It is the only way you can get to less than 2c per gallon of final nutrient solution (that I could find at least).
About claims, almost all nutrient companies will make some sort of claim about their product being “better than their competitors” and that “people who tried it got better results”. However, you seldom see evidence in proper trials of any of these matters. I always automatically discard claims that are provided without evidence when they are made by someone trying to sell me something.
Light, irrigation and CO2 are necessary contributors to yield and quality. If any of those fail or change then any comparison between nutrients is irrelevant. Plant research is specially hard due to this fact.
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Hey I have been reading over some of your posts recently and I’m curious to know, what is your educational background?
Now that extraction is imploding I’m thinking about getting back into hydroponic growing because that’s what initially got me interested in the cannabis scene.
This will sound like a completely newb-ish question but how did you learn about using tissue analysis and knowing what the readings should be for cannabis and how to change them by altering the feed?
How do you know so much about combining different salts and what will be antagonistic with what?
I do have some basic first semester organic chem knowledge and I have seen the Mulder’s Chart so it’s not completely foreign to me.
Do you have any recommendations on how can I get into all this and learn more about it?
Do you see a promising future in this type of work (not necessarily Cannabis focused)?
I really love the idea of using this type of data-centric approach to cultivation. It’s something that didn’t seem possible for cannabis last time I was growing and I always felt like I was just guessing about stuff.
Thanks.
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My degree is in production horticulture. Since then I have re-educated myself on plant nutrition, mainly following the work of Albrecht, Reams and Tainio.
It is important to note that at this point in time there is no perfect tissue sufficiency or DRIS data published for cannabis. All tissue sufficiency studies to date have been averages of crops tested by one agency, just because it’s average or normal doesn’t mean it’s correct.
I’ve developed my continually evolving targets over the years by first identifying that I was growing way better pot in soil than soilless using specialty nutrients available at the time. I did tissue analysis on those soil grown plants that were of higher quality to my customers and I. What I found was drastically different ratios compared to my hydro grown crops. Around this time is when I started looking into using a brix refractometer. Just to be clear brix is mostly considered pseudoscience by the majority of professionals in my field. But I noticed that the “better” soil grown crops were high brix. Albrecht and Reams heavily focus on soil management and ratios to grow a high brix crop, not very useful when growing soilless. Tainio focused on nutritional ratios within a plant, his findings are more useful for soilless culture. One of the key ones is that you can’t grow high brix unless potassium is higher than nitrogen.
I’ve been growing weed as a sole source of income since 2006, and got my degree in 2008. My knowledge of antagonisms and synergism specifically in cannabis has been built over that time.
The upcoming USU class would be a good place to start to understand broad concepts and the underlying reasons behind them. I do not know of any single source to learn about brix, just read and apply every publication you can get from Albrecht, Reams, and Tainio.
There will always be a future in agronomy and horticulture. It all depends on your expectations, average salary for someone with my background working full time in a tomato house is probably about $60k. To get to the $100k+ range you need to put in time with a big company like Heinz or do freelance work as a consultant. With the retraction in cannabis, I can be what many people consider expensive, so I do most stuff based on contracts where I only get paid if a clear performance target is met.
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Thanks for the reading recommendations!
I just got contracted to put together a facility. We are going with FOHSE, Agnetix or Fluence fixtures, Meter Group or Agrowtek sensor logging, Cultivation Connect smart analytics, testing at New Age Labs and Athena nutes.
I wish they would spring for someone like an on-staff agronomist that could mix nutes, but they need entry level employees that can follow a feed schedule.
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Weigh them out prepackaged bags. Then the directions are: add this entire bag to make X gallons of stock solution. Protects your ip to a minimal degree and it’s as idiot proof as anything else for the wooks
Tissue analysis would be a much more useful tool if someone was in a position to make changes.
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That makes a lot of sense in regards to pre-packaging nutes. Now that you say it, testing doesn’t seem as useful without the ability to make changes on the fly. It seems counterintuitive, but it would probably be the first place they would cut costs if something goes wrong.
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I got the test results back for the Athena Grow. Thanks @DeltaFine for sending me the sample! Twice because the USPS lost the first one for quite some time.
I have abandoned my plan to use Athena, the plants just looked horrible on it again. When I get the same result twice, I call it good. This isn’t meant to be a knock on Athena, it is obviously amazing when used in the proper conditions like @Medicine.grower is doing. I grow in Sunshine Mix and with my soft and chlorinated tap water and for whatever reason that doesn’t seem to be optimal with Athena. I’ve gone back to my old standby Jack 321 and the plants look great.
I’ll post the old Athena Bloom and the new Veg test results. As you can see not that different. You get some more N in Veg and slightly more P in Bloom.
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Those really are similar…
Thanks for getting this info!
Can I ask what your target EC or pwEC is when flowering with jacks?
I try to have my input TDS not be over 850 ppm (500 scale) and my runoff be under 1350 or so. Any higher than that and the plants usually don’t like it.
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@emdub27 could you share what ratios you like for NPKCaMgFeS etc.?
I recognize you from your other name on another website and I have learned so much from you over the years. Wondered what you liked to use these days and if it has changed from your earlier years.
I don’t run any fixed ratios. I try to achieve the tissue analysis sufficiency ranges and DRIS that I have established over the years. That data cost me and my business partners a lot to develop. For that reason is doesn’t get shared. At some point it will probably be published, but I don’t know when.
What I can tell you is that I’ve achieved the same targets and approximately the same yield at anywhere from 1.5ec to 3.5ec feed. The ratios in solution vary wildly from the lower end to the higher end to achieve the same end product. The necessary ratios also change drastically based on the environmentals. In my opinion, based on tissue and yield data over roughly 60 facilities at this point, every tissue sufficiency study published for cannabis is wrong. Every published tissue study has focused on averages, and nothing else. Cannabis is not special and it’s tissue analysis should look similar to other dicots. I’ve also never walked in to a new facility that wasn’t low on potassium.
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Here’s some info I found on DRIS, I hadn’t heard of it before:
"Nutrition and fertilization are important factors in determining fruit yield and fruit quality. There are several methods for plant nutritional status diagnosis, among them, two are relevant and named as Sufficiency Range Approach (SRA) and Diagnosis and Recommendation Integrated System (DRIS).
The DRIS method expresses results of plant nutritional diagnosis through indexes, which represent the effect of each nutrient in the nutritional balance of the plant.
The working premises for DRIS are based on: (a) the ratios among nutrients are frequently better indicators of nutrient deficiencies than isolated concentrations values; (b) some nutrient ratios are more important or significant than others; (c) maximum yields are only reached when important nutrient ratios are near the ideal or optimum values, which are obtained from high yielding-selected populations; (d) as a consequence of the stated in (c), the variance of an important nutrient ratio is smaller in a high yielding (reference population) than in a low yielding population, and to the relations between variances of high and low yielding populations can be used in the selection of significant nutrient ratios; (e) the DRIS indices can be calculated individually, for each nutrient, using the average nutrient ratio deviation obtained from the comparison with the optimum value of a given nutrient ratio, hence, as pointed by Jones (1981) and Walworth & Sumner (1987), the ideal value of the DRIS index for each nutrient should be zero.
An important limitation of these methods is that, especially in some annual crops, the established standard sampling period many times occurs too late in the growing season, so that fertilizer application will not be effective to correct a nutritional problem, or may not match the sudden symptoms of a nutritional disorder, when the producer mostly need the information (Walworht & Sumner, 1987). To overcome this problem, it would be necessary to get nutritional reference values for several maturation stages and, as a matter of fact, some of these standards have already been established for a few crops. Although simple in theory, this procedure is of difficult application."
After reading that last paragraph I understand why emdub27 doesn’t freely share the ranges he has established for Cannabis.
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So what dicots should I be looking at to get an idea of what sufficiency ranges and ratios would most apply to cannabis? I know @emdub27 suggested Tomato’s and, peppers as a start. I did check out a few published articles that gave ratios for Tomato’s but, the Ca usually seems to high to directly apply to Cannabis. I couldn’t find a lot of published ratios on peppers.
Tomatoes usually have Ca compositions of youngest mature leaves of around 1-2%, this is common to most dicots (see here HS964/EP081: Plant Tissue Analysis and Interpretation for Vegetable Crops in Florida). Averages for most labs on cannabis will usually be above 4% Ca.
However, Ca in tissue depends strongly on the age of the leaves and as cannabis leaves grow old, they usually accumulate very high amounts of Ca. The youngest mature leaves in week 8+ of flower are usually several weeks old and can be even 10% Ca.
Since people send leaf tissue from all over flower for analysis, averages tend to be much higher and people take this to mean that a young cannabis plant should have Ca values this high in leaves, which is wrong from a plant physiology perspective.
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I would also like to note that in terms of nutrient interactions cannabis behaves a bit different to other dicots. I have developed a nutrient interaction chart for cannabis with my clients that has taken over 500 tissue samples to figure out to a high certainty (like a Mulder’s chart but with actual numbers to represent the strength of relationships). Several of the interactions commonly assumed to be facts are different in this plant. For example the interactions between Zn and P.
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My tissue data agrees with everything @danielfp said in the last 2 posts. It is also pretty awesome that he has more or less correlated DRIS data to feed ratios. I’ve never attempted to do that.
@SeymourGreen a combination of pepper and tomato data is pretty much where we are. But @danielfp pointed out the ion interactions are quite different and as a result you can’t look at pepper or tomato feed data.
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Man this shits hard lol! It sucks from my perspective because I’m just a simple home grower. I’m in a no rec state, trying to grow cannabis hydroponically, that tastes as good as the weed I grew outside in soil mixes, picked up from the growers bible and high times articles, 25 years ago. I don’t have access to tissues data, and probably couldn’t afford it if I did. This is where @danielfp idea for his website and feed ratios based on DRIS and plant sufficiency, would be like an epiphany for me.
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Looking over some charts I see that si antagonizes ca, I’m now finally using agsil and was wondering what’s the most recommended before it starts to have an effect on calcium?
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