The Myth of Gypsum Magic

[Old Uncle Ben]

Biggest troubles I've had from excess gypsum have been,

1.) increased sulfur, sometimes to the point of off the charts (exaggeration to a degree, but high S), especially if using other sources of sulfur in my mixes, to include bokashi bran, etc. And some fertilizers already have a Sulfur punch onboard.

2.) The quality of organic or other amendments can vary greatly, so testing for the ph of the product before mixing it is important. I've used (I think it was Epsoma brand) gypsum and had it affect ph negatively, creating issues with too much acidic value in the subsequent testing. Down to Earth's gypsum that I last tested was more a neutral ph.

I still use gypsum to increase Ca, but I use it more sparingly.

Gypsum is pH neutral. If your medium is acidic it's got to be something else going on. There are plenty of crappy pH meters on the market too. I use Anaheim Scientific and calibrate it before a test with solution.

Folks need to test soil pH correctly. For starts, YOU MUST use de-ionized water, lab quality. You can buy it off ebay, Amazon, etc. No, distilled won't cut it as it still contains ions, mostly organic. Dump some soil into a clean glass jar, add about double the amount of water, shake, let it settle a bit and stick your probe in using an accurate meter.

My plants get Ca from my well water or sources like Dyna-Gro Foliage-Pro, 9-3-6.

FWIW, I often link folks to Dr. Chalker in other gardening forums, both cannabis and fruit or veggie. She's a solid myth buster, and God do we need more of those in cannabis forums.

Uncle Ben

 

[moose eater]

Gypsum is pH neutral. If your medium is acidic it's got to be something else going on. There are plenty of crappy pH meters on the market too. I use Anaheim Scientific and calibrate it before a test with solution.

Folks need to test soil pH correctly. For starts, YOU MUST use de-ionized water, lab quality. You can buy it off ebay, Amazon, etc. No, distilled won't cut it as it still contains ions, mostly organic. Dump some soil into a clean glass jar, add about double the amount of water, shake, let it settle a bit and stick your probe in using an accurate meter.

My plants get Ca from my well water or sources like Dyna-Gro Foliage-Pro, 9-3-6.

FWIW, I often link folks to Dr. Chalker in other gardening forums, both cannabis and fruit or veggie. She's a solid myth buster, and God do we need more of those in cannabis forums.

Uncle Ben

I individually tested the Epsoma brand gypsum (very acidic in that sample's case), and I tested the DTE gypsum, and it was neutral at 7 where it was supposed to be.

That was my point. Quality of amendments can vary greatly.

Consider how difficult it's been to keep the human food supply clean and labeled accurately, let alone the dog and cat food supplies. Now ask how many people are standing by in white hats testing accuracy in labeling in organic amendments.

I've tested all kinds of amendments; some through labs and some simply via ph testing dish. There's a lot of garbage on the market where garden amendments are concerned, and no one is going to prison for selling poorly labeled gardening amendments. Even if maybe they ought to, for the fraud it constitutes.

 

[G.O. Joe]

It's not bullshit for half the world's farmland. There's much published,
https://sci-hub.se/10.2136/sssaj1999.634891x

for example, showing the benefit to acid soils. A mixture of dolomite and gypsum is probably best.

 

[Old Uncle Ben]

I individually tested the Epsoma brand gypsum (very acidic in that sample's case),

Wouldn't touch the Espoma brand. It is shit. Don't know how many times in fruit forums, organic only folks, have screwed up their citrus trees with the Espoma Citrus Food. That crap doesn't have the correct NPK ratio and none of the micros citrus requires, like Mn, Fe, and Zn

If folks fall for the bird feathers and green sand crap, then they deserve what they get for being so naive and stupid.

Uncle Ben

 

[Old Uncle Ben]

It's not bullshit for half the world's farmland. There's much published,
https://sci-hub.se/10.2136/sssaj1999.634891x

for example, showing the benefit to acid soils. A mixture of dolomite and gypsum is probably best.

If you have a limiting acid soil then quick lime (calcium hydroxide) is a quick albeit temporary cure. The buffering effect will be short lived. No different than trying to lower the pH of limey soils with sulfuric acid or sulfur powder. Expensive and futile cure. Best to match the soil's profile with the right crop.

Uncle Ben

 

[YellowCanaryConsulting]

Myth? Did someone say myth? I love myths!

Gypsum Is the single best addition to my gardens all thanks to the advise of @slownickel. All the haters can keep on talking but slow lives it and has helped thousands grow nutrient dense crops. The Calcium is king.

Is Slownickel the reason why every grow I look at the past 10 years has thick leathery ribbed blue-gray leaves with white midribs purple petioles & roasted margins? Isn't he the guy that bought up all the athletic field marker for next to nothing and sells it as specialized foliar spray that oxidizes the plants leaf flora and doesn't travel through the phloem whatsoever?

Douglass Curtis has the idea. Spoon feed soluble calcium aka athletic field marker plus citric or ethanoic. Otherwise you won't be able to get rid of the shit come finish. Personally I won't feed calcium without feeding everything that calcium antagonizes, which is plenty.

You will go broke at finish trying to cram enough potassium sulfate into the plant after turning your soil into limestone. "Oh no the water runs out the sides of me fabric bag, and what's this white crust all over me fabric bag". Too late for phosphorus by the time you've heard more calcium is good for buds, especially indoors under the gavita led standard. Sap tests show that not even the sulfur is being taken up in these hypercalcemic soils everyone with a nute startup is pushing on weed nute victims.

The congenital epigenetic impact the bro fertilizer community has had on the cannabis gene pool is devastating, from the fact breeders cull plants that refuse to adapt to hypercalcemic nutrient regimens, choosing your Blue Chalk Dreamsicles over Sour Blueberry Skunkbutts. To the shift in lipid profiles caused by driving nitrogen with calcium but not driving calcium with boron, resulting in all the dough batter stale muffin expressions in plants that typically smelled like carboxylic acids and low carbon thiols for thousands of years. To the fact that sweet and sour associations no longer correlate with P:K input when sugar/acid ratios were commonly steered to match cultivar.

- YouTube

Enjoy the videos and music that you love, upload original content and share it all with friends, family and the world on YouTube.

youtube.com

Doesn't appear to be toxic, Bruce? Then why the hell is Cannabis unable to take up potassium when Ca is 8% in leaf tissue? And where is that calcium in leaf tissue? What percentage is exogenous, being exuded into trichome structure, what percentage is in sap?

Anyone thinking about selling chalk or drywall as fertilizer: Turn off the youtubes, stop stalking grow forums for feedback on how to scam nute victims, and read a book once in a while. Be a good actor not someone who talks circles around potheads and cancer patients. Live in reality, not in dogma that's been proven untrue long ago. Societies problem, leaders staying one lesson ahead of followers, a society like this doesn't last long when the lessons are not based in observable reality. Example: Women don't have testicles, I don't care how friendly and well studied the messenger is. You're destroying society.

Unmetabolized excess calcium is the biggest detriment I've found to Cannabis quality. Especially when it binds with carbonate and builds trichome walls. I bet everyone pushing excess calcium nutes as a trend also sells silica sprays and hippy pesticides, you're gonna need em growing in soil that turns white when it dries out. Enjoy the pretty white roots with no fine hairs and no colonization. They grow like that trying to get away from the lime deposit they've been forced into.

Eventually someone will figure out how to turn Gypsum into calcium acetate, so you can keep the sulfur. Not sure who's overdosing on sulfur. Guys drinking sesame oil and shitting in their soil beds I recon.

Or better yet, the guys who bought up all the basic slag will eventually figure out how to turn it into a bottled product. But then they can't sell you TM7.. Hmm... There's always a downside to progression, isn't there.

Too long didn't read: Why are people pushing excess calcium when all it does is lock out shit and ruin the expression of the plant? Because some guy from the ag sector talked about tomatoes on a podcast, then some stoner started his own podcast and repeated it about Cannabis. TalkingTomatoes, that might be the name of my new podcast..

 

[moose eater]

Myth? Did someone say myth? I love myths!



Is Slownickel the reason why every grow I look at the past 10 years has thick leathery ribbed blue-gray leaves with white midribs purple petioles & roasted margins? Isn't he the guy that bought up all the athletic field marker for next to nothing and sells it as specialized foliar spray that oxidizes the plants leaf flora and doesn't travel through the phloem whatsoever?

Douglass Curtis has the idea. Spoon feed soluble calcium aka athletic field marker plus citric or ethanoic. Otherwise you won't be able to get rid of the shit come finish. Personally I won't feed calcium without feeding everything that calcium antagonizes, which is plenty.

You will go broke at finish trying to cram enough potassium sulfate into the plant after turning your soil into limestone. "Oh no the water runs out the sides of me fabric bag, and what's this white crust all over me fabric bag". Too late for phosphorus by the time you've heard more calcium is good for buds, especially indoors under the gavita led standard. Sap tests show that not even the sulfur is being taken up in these hypercalcemic soils everyone with a nute startup is pushing on weed nute victims.

The congenital epigenetic impact the bro fertilizer community has had on the cannabis gene pool is devastating, from the fact breeders cull plants that refuse to adapt to hypercalcemic nutrient regimens, choosing your Blue Chalk Dreamsicles over Sour Blueberry Skunkbutts. To the shift in lipid profiles caused by driving nitrogen with calcium but not driving calcium with boron, resulting in all the dough batter stale muffin expressions in plants that typically smelled like carboxylic acids and low carbon thiols for thousands of years. To the fact that sweet and sour associations no longer correlate with P:K input when sugar/acid ratios were commonly steered to match cultivar.

- YouTube

Enjoy the videos and music that you love, upload original content and share it all with friends, family and the world on YouTube.

youtube.com

Doesn't appear to be toxic, Bruce? Then why the hell is Cannabis unable to take up potassium when Ca is 8% in leaf tissue? And where is that calcium in leaf tissue? What percentage is exogenous, being exuded into trichome structure, what percentage is in sap?

Anyone thinking about selling chalk or drywall as fertilizer: Turn off the youtubes, stop stalking grow forums for feedback on how to scam nute victims, and read a book once in a while. Be a good actor not someone who talks circles around potheads and cancer patients. Live in reality, not in dogma that's been proven untrue long ago. Societies problem, leaders staying one lesson ahead of followers, a society like this doesn't last long when the lessons are not based in observable reality. Example: Women don't have testicles, I don't care how friendly and well studied the messenger is. You're destroying society.

View attachment 18831942

Unmetabolized excess calcium is the biggest detriment I've found to Cannabis quality. Especially when it binds with carbonate and builds trichome walls. I bet everyone pushing excess calcium nutes as a trend also sells silica sprays and hippy pesticides, you're gonna need em growing in soil that turns white when it dries out. Enjoy the pretty white roots with no fine hairs and no colonization. They grow like that trying to get away from the lime deposit they've been forced into.

Eventually someone will figure out how to turn Gypsum into calcium acetate, so you can keep the sulfur. Not sure who's overdosing on sulfur. Guys drinking sesame oil and shitting in their soil beds I recon.

Or better yet, the guys who bought up all the basic slag will eventually figure out how to turn it into a bottled product. But then they can't sell you TM7.. Hmm... There's always a downside to progression, isn't there.

Too long didn't read: Why are people pushing excess calcium when all it does is lock out shit and ruin the expression of the plant? Because some guy from the ag sector talked about tomatoes on a podcast, then some stoner started his own podcast and repeated it about Cannabis. TalkingTomatoes, that might be the name of my new podcast..

I could scan and show soil tests from well-known labs with sulfur being way too high in mixes, contributed to by a number of added amendments. I never shit in my soil beds.

Pomposity crimps discussion though, that's for sure.

Biomin provides a 1-0-0 in a liquid calcium additive with no mag onboard,. as I had magnesium excesses as well.

And despite the calcium levels I was running, I still had potassium efficiency to excess.

Most of even the best commercial 'organic' worm casting run an excess in both magnesium and potassium. No, really. I've tested a number of them through the local soil and water outlet, sending out to the well-known labs that provided my sample testing for my soilless mixes, doing both Mehelich III and simple H2O extraction.

 

[Tynehead Tom]

Gypsum Is the single best addition to my gardens all thanks to the advise of @slownickel. All the haters can keep on talking but slow lives it and has helped thousands grow nutrient dense crops. The Calcium is king.

yes ...... first I have to give credit to @rykus , who isn't around much anymore but is still out there doing his thing last I heard. His advice led me to begin adding granulated gypsum to my arsenal although powdered gypsum is what is used in the recipes I think.
It's not about blindly adding gypsum and expecting miracles , it is abut tailoring your soil or feed so the required calcium and sulfer is availlable. If your soil or feed already has the desireable calcium levels availlable throughout the grow then applying more might be pointless.
Rykus turned me on to slownickle but I have a hard time following him. I also use what i refer to as the Tom Hill basic water only recipe for my summer greenhouse runs. The recipe calls for 5 pounds of granulated gypsum per 110 gallons of soil mix. I use this mix every season with excellent results and the proof is in my grow and show every summer/fall.
Indoors I use gyspum when it is required and some strains need more or less calcium. The calcium hogs get gypsum in the waterings, others may not. I also water my final weeks with gypsum and molasses and I have witnessed the results indoors and out and will continue the practice.

I'm no university degree plant guy but I can read my plants and strains and what they respond to and will continue to keep and use gypsum where my own data shows it made a difference.

edit to add.... I don't use the powdered field marker type gypsum..... I use agricultural granulated

 

[Old Uncle Ben]

Myth? Did someone say myth? I love myths!



Is Slownickel the reason why every grow I look at the past 10 years has thick leathery ribbed blue-gray leaves with white midribs purple petioles & roasted margins? Isn't he the guy that bought up all the athletic field marker for next to nothing and sells it as specialized foliar spray that oxidizes the plants leaf flora and doesn't travel through the phloem whatsoever?

Douglass Curtis has the idea. Spoon feed soluble calcium aka athletic field marker plus citric or ethanoic. Otherwise you won't be able to get rid of the shit come finish. Personally I won't feed calcium without feeding everything that calcium antagonizes, which is plenty.

You will go broke at finish trying to cram enough potassium sulfate into the plant after turning your soil into limestone. "Oh no the water runs out the sides of me fabric bag, and what's this white crust all over me fabric bag". Too late for phosphorus by the time you've heard more calcium is good for buds, especially indoors under the gavita led standard. Sap tests show that not even the sulfur is being taken up in these hypercalcemic soils everyone with a nute startup is pushing on weed nute victims.

The congenital epigenetic impact the bro fertilizer community has had on the cannabis gene pool is devastating, from the fact breeders cull plants that refuse to adapt to hypercalcemic nutrient regimens, choosing your Blue Chalk Dreamsicles over Sour Blueberry Skunkbutts. To the shift in lipid profiles caused by driving nitrogen with calcium but not driving calcium with boron, resulting in all the dough batter stale muffin expressions in plants that typically smelled like carboxylic acids and low carbon thiols for thousands of years. To the fact that sweet and sour associations no longer correlate with P:K input when sugar/acid ratios were commonly steered to match cultivar.

- YouTube

Enjoy the videos and music that you love, upload original content and share it all with friends, family and the world on YouTube.

youtube.com

Doesn't appear to be toxic, Bruce? Then why the hell is Cannabis unable to take up potassium when Ca is 8% in leaf tissue? And where is that calcium in leaf tissue? What percentage is exogenous, being exuded into trichome structure, what percentage is in sap?

Anyone thinking about selling chalk or drywall as fertilizer: Turn off the youtubes, stop stalking grow forums for feedback on how to scam nute victims, and read a book once in a while. Be a good actor not someone who talks circles around potheads and cancer patients. Live in reality, not in dogma that's been proven untrue long ago. Societies problem, leaders staying one lesson ahead of followers, a society like this doesn't last long when the lessons are not based in observable reality. Example: Women don't have testicles, I don't care how friendly and well studied the messenger is. You're destroying society.

View attachment 18831942

Unmetabolized excess calcium is the biggest detriment I've found to Cannabis quality. Especially when it binds with carbonate and builds trichome walls. I bet everyone pushing excess calcium nutes as a trend also sells silica sprays and hippy pesticides, you're gonna need em growing in soil that turns white when it dries out. Enjoy the pretty white roots with no fine hairs and no colonization. They grow like that trying to get away from the lime deposit they've been forced into.

Eventually someone will figure out how to turn Gypsum into calcium acetate, so you can keep the sulfur. Not sure who's overdosing on sulfur. Guys drinking sesame oil and shitting in their soil beds I recon.

Or better yet, the guys who bought up all the basic slag will eventually figure out how to turn it into a bottled product. But then they can't sell you TM7.. Hmm... There's always a downside to progression, isn't there.

Too long didn't read: Why are people pushing excess calcium when all it does is lock out shit and ruin the expression of the plant? Because some guy from the ag sector talked about tomatoes on a podcast, then some stoner started his own podcast and repeated it about Cannabis. TalkingTomatoes, that might be the name of my new podcast..

Tell us how you feel LOL. Hey Preacher Man, how about slinging some shit on the good ol cannabis cure all - epsom salts.

Good one,
Uncle Ben

 

[Old Uncle Ben]

95% of nutritional issues are mis-diagnosed by growers. So what do they do trying to fix The Problem? Throw more crap at their plants that only exacerbates the issue.

No worry, probably the only carnie that loves you more is Mike Lindell.

Sleep well 2.0 ers.

UB

 

[Old Uncle Ben]

"Biomin® Calcium contains complexed calcium designed for..." https://jhbiotech.com/docs/Biomin-Calcium-Flyer.pdf

Well, if it's "complexed" then it's got to be good. These con artists....I swear.

UB

 

[Old Uncle Ben]

Indoors I use gyspum when it is required

What indication or flag would that be?

 

[troutman]

The soil outside in my guerilla spots have low pH cause of the local mines.
So adding limestone to the soil creates gypsum when it all reacts together
during the neutralization process.

 

[Tynehead Tom]

What indication or flag would that be?

signs that the plant is lacking calcium??
I've been doing this cannabis growing thing since 89 so I like to think I have a good feel for reading my plants and trying to diagnose thier needs. I run multi strain crops from seed routinely and I generally have close to or right at 110 plants at any given time during my indoor season. It affords me the ability to view many many plants that run thru my methods. I'm not the greatest grower out there but I know I grow excellent cannabis.
Running high numbers of multi strains on a "one size fits all" feeding regimen will quickly show the grower that there is no "one size fits all" regimen and the nutrients and other inputs need to be tweaked as needed and sometimes on indivual plants.
So with the numbers and the high number of strains running through my rooms..... I would say yes, inputs of AG Gypsum have shown clear benfits in my grows.*** Many of these studies we read or get posted aren't even run on Cannabis over multiple seasons, multiple strains so I take them all with a grain of salt. Experience is the greatest teacher and the learning never ends. My experience so far has been that Gypsum, used when needed, benefits my cannabis gardens.
As a routine, I grow in Sunshine Mix #4 soilless mix. I fortify every batch of soil indoors with AG Gypsum and Dolopril (dolomitic lime). Works for me.

 

[G.O. Joe]

If you have a limiting acid soil then quick lime (calcium hydroxide) is a quick albeit temporary cure. The buffering effect will be short lived. No different than trying to lower the pH of limey soils with sulfuric acid or sulfur powder. Expensive and futile cure. Best to match the soil's profile with the right crop.

What a coincidence, the paper which you quoted happens to be all about expense and the long term effects of gypsum on crop yield and subsoil chemical properties.

Even limewater is too hot unless it's delivered very dilute by irrigation. It makes a hot topsoil and does nothing below. People use limestone instead because it's the preferred plan. Wheat or corn are likely seen as more valuable than shitty tea and blueberries.

The reasoning for dolomite+gypsum is really about yield in typical acid soil rather than pH movement. The pH is lowered slightly by the gypsum treatment in the quoted paper. Gypsum or more specifically sulfate affects the availability of soil Al in a particular way which should not be expected of other forms of Ca.

The <5.5 pH soils most likely to benefit are the most likely to be deficient in Ca, so actual problems from oversupply is an application fuckup rather than a theoretical one.

It's no accident that there's calmag - absolutely overused by indoor growers, especially if they start with hard water - instead of cal and mag, promix has dolomite mixed in instead of straight limestone, almost all the garden store lime is dolomitic, and so on. Dolomitic lime and products made from it are also the cheapest and most soluble, but this is secondary to the fact that Ca should be paired with a certain minimum amount of Mg.

 

[moose eater]

What a coincidence, the paper which you quoted happens to be all about expense and the long term effects of gypsum on crop yield and subsoil chemical properties.

Even limewater is too hot unless it's delivered very dilute by irrigation. It makes a hot topsoil and does nothing below. People use limestone instead because it's the preferred plan. Wheat or corn are likely seen as more valuable than shitty tea and blueberries.

The reasoning for dolomite+gypsum is really about yield in typical acid soil rather than pH movement. The pH is lowered slightly by the gypsum treatment in the quoted paper. Gypsum or more specifically sulfate affects the availability of soil Al in a particular way which should not be expected of other forms of Ca.

The <5.5 pH soils most likely to benefit are the most likely to be deficient in Ca, so actual problems from oversupply is an application fuckup rather than a theoretical one.

It's no accident that there's calmag - absolutely overused by indoor growers, especially if they start with hard water - instead of cal and mag, promix has dolomite mixed in instead of straight limestone, almost all the garden store lime is dolomitic, and so on. Dolomitic lime and products made from it are also the cheapest and most soluble, but this is secondary to the fact that Ca should be paired with a certain minimum amount of Mg.

So what if the mix already has an abundant supply of magnesium?

 

[G.O. Joe]

The question is will that continue to be the case if you add a mobile form of Ca without adding some Mg. Or, can mined dolomite dissolve fast enough to cause Mg poisoning, whether no-till or not.

But if you really want to avoid Mg, calcitic limestone+gypsum is still probably better than gypsum alone. We're not talking about enough of either to eliminate available Al+++ from the root zone completely, just to take the edge off.

 

[moose eater]

The question is will that continue to be the case if you add a mobile form of Ca without adding some Mg. Or, can mined dolomite dissolve fast enough to cause Mg poisoning, whether no-till or not.

But if you really want to avoid Mg, calcitic limestone+gypsum is still probably better than gypsum alone. We're not talking about enough of either to eliminate available Al+++ from the root zone completely, just to take the edge off.

Thanks.

I use very limited amounts of both gypsum and dolomite lime, relying more heavily on low-magnesium garden lime mined locally; about 95% lime.

There's a bit of zeolite in my mixes these days, and other CE boosters.

The magnesium and sulfur, as well as salts, have been found to come from several sources, and I spent a good amount of time purposefully trying to decrease those things in the mix that carried inordinate and/or redundant amounts of those items.

I also have fairly hard H2O (well water) with a total hardness of about 380 last time I did a serious analysis for toxins, heavy metals, hardness, minerals, etc. about 95ppm calcium carbonate, if I recall correctly.

 

[experienced]

Pomposity crimps discussion though, that's for sure.

"Pomposity ..."? Yes, that was the word I was looking for also.

 

[moose eater]

"Pomposity ..."? Yes, that was the word I was looking for also.

When my garden was poisoned with round up I immediately turned the ground under my trees white with gypsum then watered like crazy before applying fulvic acid. I saved most of my trees.

I have no doubt gypsum is useful for ridding soil of excess minerals. This was proven in Holland during the 1950's (I think) after the North Sea flooded farmland and there was a need to flush out (whether by precipitation or drainage) sodium.

I also need to use it to remove excess magnesium from my soil.

When seeking advice re flushing out roundup from soil a nutrient specialist told me gypsum would acidify soil due to the presence of sulfur. Completely contrary to this the gypsum bag had on it 'will not alter soil ph'.

I use gypsum mostly to improve soil drainage ... and it does.

If folks used what they know to help others in ways that can be understood, rather than using cryptic knowledge, with understandable details withheld as an opportunity to buff egos and belittle others who are wanting to know, then pomposity wouldn't have been the word used.

Elitists and snobs exist in all walks in life. Too many, frankly. Impressing others is typically their goal. But it's not the outcome as a rule.