The Cal-Mag of my dreams?

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jerrytheplater
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Re: The Cal-Mag of my dreams?

Post by jerrytheplater »

MikeInOz wrote: Fri Feb 17, 2023 12:14 am
jerrytheplater wrote: Thu Feb 16, 2023 3:57 am


That figure shows an optimum soil P level down in the 20 ppm range for both crops to give 90-100% relative yield. But each show continued 90-100% relative yield even out to 70 ppm P in the soil.
But is that soluble P or insoluble P? In other words is it available to the plants or just the total soil P content?
Also, for that crop, the 20 to 70 ppm range could be the optimum range? There will be a level where yield will start to decline as P increases but I have no idea what that might be in that situation.
Mike
In the text of the article dealing with Figure 1 it says "plant available P" so it is soluble P that is being tested.

The figure plainly shows a blue band noted as "Optimum class". The caption of the figure says, "The blue bar indicates the range of P sufficiency." So it is saying the roughly 15-22 ppm soluble P is the sufficient amount to produce optimum crop yields for corn and soybeans.

The point I saw from this chart is that optimum crop yields are still obtained for these two crops even when up to 4 times the optimum P is present and available to the plant.

New information not related to this article:

I am working part time with my friend in his commercial greenhouses. He's been in the ornamental, vegetable field for at least 25 years since he was a teenager. He now owns his own greenhouses. They are nowhere near as big as where he was. But he says if he can go to all retail he will be in a much better place. He knows he can't compete with the big growers where he was before. Prior to this, he was Chief Grower at a 15 acre greenhouse producing about 1/2 million flats a season. I've been in that greenhouse and it is really high tech. One person can water the entire greenhouse in about 3 hours. The seeders are amazing, picking up one seed per cell via vacuum and placing it right in the middle. The transplanting machine is like a big pantograph. It grabs plugs and expands to place each plug in the cells in the flat. Women fill in skips manually where no plant existed for the machine to pick up.

Anyway, I asked him today if he ever heard of high P levels causing any bad effects in his plants. He said it will cause the plants to stretch. Internode distance increases. He said he always uses low P fertilizers except for the first few weeks after transplanting Chrysanthemums and if he ever needs to boost New Guinea Impatiens due to cloudy periods. Otherwise he uses low P ferts.

A big one he uses is Dyna-Gro Foliage-Pro which is in US terms 9-3-6, and elemental 9-1.3-5. That is the one I use after boosting it to the 1-0.4-1.5 ratio with Mono Potassium Phosphate and Potassium Sulfate. It comes out at 9-3.6-13.5. I water at 50 ppm N.
Jerry Smith
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Steve Johnson
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

Stupid question...

"Internode distance" -- in cacti, is that the distance between individual tubercles?
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DrPlantDaddy
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Re: The Cal-Mag of my dreams?

Post by DrPlantDaddy »

Steve Johnson wrote: Fri Feb 17, 2023 5:56 am Stupid question...

"Internode distance" -- in cacti, is that the distance between individual tubercles?
Yeah, the distance between areoles would be the reasonable internode distance measurement for cacti.
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Re: The Cal-Mag of my dreams?

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DrPlantDaddy wrote: Fri Feb 17, 2023 6:16 amYeah, the distance between areoles would be the reasonable internode distance measurement for cacti.
That's what I thought -- thanks, Kane!
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MrXeric
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Re: The Cal-Mag of my dreams?

Post by MrXeric »

I guess I've been too trusting on the old xerophilia website. :) Thanks for finding an alternative source for these magazines. I didn't think of checking the cactuspro library.

But I agree, Mr. Panco certainly has his biases! Though I do tend to agree with them; I prefer to mimic habitat growth habits when possible! I think what is missing (or is neglected) from The Stone Eaters article is a good fertilization regimen. He mentions often that "nature does not offer gifts" when talking about macroelements (NPK) and that fertilization should be limited to providing micronutrients only. But as we know, desert soils may be poor in nitrogen and phosphorus, those elements are not completely absent, and even regenerate in the case of nitrogen. He does use leaf mold, but that is not a significant source of N I believe? so without fertilization his mix is more punishing than nature!
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Re: The Cal-Mag of my dreams?

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MrXeric wrote: Fri Feb 17, 2023 6:21 am I guess I've been too trusting on the old xerophilia website. :) Thanks for finding an alternative source for these magazines. I didn't think of checking the cactuspro library.

But I agree, Mr. Panco certainly has his biases! Though I do tend to agree with them; I prefer to mimic habitat growth habits when possible! I think what is missing (or is neglected) from The Stone Eaters article is a good fertilization regimen. He mentions often that "nature does not offer gifts" when talking about macroelements (NPK) and that fertilization should be limited to providing micronutrients only. But as we know, desert soils may be poor in nitrogen and phosphorus, those elements are not completely absent, and even regenerate in the case of nitrogen. He does use leaf mold, but that is not a significant source of N I believe? so without fertilization his mix is more punishing than nature!
Glad I could find that for you! In case you didn't see my advisory on the General forum, here's DaveW's response:
DaveW wrote: Thu Feb 16, 2023 10:34 am It has been replaced by Carpophyma Steve by the same editor that is a curious mixture of articles, but containing a few cactus and other succulent ones. I preferred the plant dedicated original.

https://cactiguide.com/forum/viewtopic.php?t=44658

I think CactusPro will list them as long as it continues itself. The flags indicate the language the publication is in.

https://www.cactuspro.com/biblio/en:accueil
When Eduart announced the Stone Eaters Special on the forum in 2013, I read it or at least tried to. Seemed awfully confusing and not well-written, although I instinctively felt that something wasn't right concerning the gist of the author's arguments. I think most habitat cacti look ugly, but that's just my personal opinion, and I fully respect growers who have different opinions on the matter. If we all thought, felt, and believed the same way, the world would be a pretty boring place. :D
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DrPlantDaddy
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Re: The Cal-Mag of my dreams?

Post by DrPlantDaddy »

Steve Johnson wrote: Fri Feb 17, 2023 6:20 am That's what I thought -- thanks, Kane!
Of course, and I meant to add, it was a great question! Not at all obvious or how I may often think of that distance in other plants like the herbs that nursery owner grows until I stopped to think about the question. But, now I also wonder if high P will cause that internode distance in cacti to respond similarly as to those herbs, albeit at a slower rate.

Just to chime in, although I’ve admittedly not read the entire thread so am likely overlooking a lot of context- I prefer to fertilize with a low P fertilizer and I add commercial mycorrhizae to my soil. Anytime I repot, I notice great colonization on the roots and so far have avoided nutrient issues. That said, I’m still a novice to the hobby just a handful of years in, so my collection is still pretty young and sample size is low. But it’s fun to mess around with these approaches.
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Steve Johnson
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

DrPlantDaddy wrote: Fri Feb 17, 2023 7:56 amOf course, and I meant to add, it was a great question! Not at all obvious or how I may often think of that distance in other plants like the herbs that nursery owner grows until I stopped to think about the question. But, now I also wonder if high P will cause that internode distance in cacti to respond similarly as to those herbs, albeit at a slower rate.
I tend to be precise in the terminology I use, and since internode distance is a term that's new to me, I'll start using it as a more accurate way to describe what I see. Jerry was onto something there, so thanks to the both of you for that. I may have a nice example for demonstrating the term "in action" with a Copiapoa tenuissima in my collection. Unfortunately no time for that now, but I'll post the before-and-after photos over the weekend. In the meantime, here's a bit of shameless self-promotion...

If you haven't seen it yet, check this out:

viewtopic.php?t=47603

Enjoy!
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Re: The Cal-Mag of my dreams?

Post by DrPlantDaddy »

Steve Johnson wrote: Fri Feb 17, 2023 9:27 am In the meantime, here's a bit of shameless self-promotion...

If you haven't seen it yet, check this out:

viewtopic.php?t=47603

Enjoy!
I had not seen it, thanks for sharing! Fantastic and thorough write-up. Cheers!
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

DrPlantDaddy wrote: Fri Feb 17, 2023 4:44 pm
Steve Johnson wrote: Fri Feb 17, 2023 9:27 am In the meantime, here's a bit of shameless self-promotion...

If you haven't seen it yet, check this out:

viewtopic.php?t=47603

Enjoy!
I had not seen it, thanks for sharing! Fantastic and thorough write-up. Cheers!
You're welcome, and I hope you'll get something useful out of it! :D
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Re: The Cal-Mag of my dreams?

Post by jerrytheplater »

I'm getting tempted to grow a bunch of seedling Frailea parviflora I have as an experiment. They are growing around the mother plants and I need to repot to get them out. They've been seeing fertilizer in a 1-0.4-1.5 ratio since they started growing last June. I would make up a much higher P fertilizer, maybe even 4X what they've been seeing, just to see what happens. I'd grow others at the regular fertilizer rate.
Jerry Smith
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45 inches (114 cm) rain equivalent per year, approx. evenly spread per month
2012 USDA Hardiness Zone 6b: -5F to OF (-20C to -18C) min.
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MikeInOz
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Re: The Cal-Mag of my dreams?

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Steve Johnson wrote: Thu Feb 16, 2023 4:07 am
MikeInOz wrote: Thu Feb 16, 2023 1:51 amI only skimmed the article Steve because I have to surrender the computer, but I have found a couple of speculative nonsense statements. For example, the Astro with lots of flower buds. It obviously has not been ''over fertilized'' looking at the plant itself, which appears normal in every way
- not bloated - not stretched - a good even covering of scales and areoles. So clearly there is another reason for all the flower buds. Another statement where ''this is the way Mammillaria schumanii is supposed to look.'' Says who? I certainly would not want mine to look like it's close to death. But maybe that's just me.....
Hi Mike,

Certainly not a high priority, but when you can go through those articles at your leisure, I think you'll concur with a couple of things I noticed:
  • A dismissive attitude on the part of Dag Panco toward cacti that are properly fed by growers who know what they're doing. I wouldn't want my cacti looking like they're on death's door either.
  • Neither author seems to know much (if anything) about the role of nutrients available to cacti under cultivation when growers use ferts that are well-balanced and include a full spectrum of all nutrients.
With respect to Mr. Panco, I do see examples of what seem to be abnormal growth in his article. What I don't see are precise descriptions of what caused the abnormalities -- "a plant influenced by an excess of fertilizers" tells us nothing. What I also don't see -- examples of cacti being grown with excessive P in the fert. Since your eyes are much better-trained than mine, maybe you do. If so, point me to the pages where you see them, and I can pull the photos out from the PDF for reference.

Why am I making such a big deal out of all this? Here's why -- from Part 1 of my Fertilizers Explained presentation:
Steve Johnson wrote: Sun Jan 22, 2023 6:53 am NPK ratio

This ratio determines whether you have well-balanced or unbalanced proportions of N, P, and K in your fert. The ideal NPK ratio for cacti and succulents is 1:0.4:1.1-1.7. Contrary to what you may have heard or read elsewhere, high-Phosphorus ferts should be avoided -- when P is higher than N, poor root growth and abnormal stem growth will be the eventual consequence of the plant's longterm exposure to a high-P fert.
I'm not satisfied with that because I don't think it's specific enough. Besides, "show and tell" would be better than making do with simply "tell" -- if I can include photographic examples of what cacti exhibiting the signs of excessive P look like, growers will know what to look for in case their cacti have those problems. And if they do, they can look for a lower-P fert to correct the situation before the problems become even more of a problem over time.
Just a few thoughts on the articles.
The over production of flowers (pages 83 and 88) attributed to ''over fertilization'' ( whatever that is) does not seem plausible.
To me, it looks more like some kind of hormone issue which is causing that freak flower production from new and old areoles. Whether the plants have been given some unknown substance, or whether it was in the water or substrate I don't know. But ''over fertilization would not cause it as far as I know. Other than the flowers, the Astrophytum for example, seems perfectly normal and does not show signs of being over fed.
As for the stone eaters article, I don't think the author has given much consideration to the fact that cacti in the habitat are not confined to a pot but are free to form extensive root systems to find nutrients they require. In natural systems, as a nutrient is removed by the plant it will get replaced. It should be remembered that the almost limitless surface area surrounding the plants will gather many nutrients during rain and re-charge what has been taken by the plant roots. That's why plants in the habitat can continue to grow well (given enough water). Nutrients move around a lot in nature but they are sooner or later depleted in pots unless we add more of them. If you imagine a cactus growing out of crack in what seems to be solid rock, you need to take the whole hill or mountain into consideration and realize that when it rains, water rich in dissolved nutrients will be channeled into these cracks. So the plants end up seeing nutrients from far and wide and not just the rocks they are attached to.
Another way nutrients reach the plants .... After rain the soil water begins to evaporate from the surface. As it does it draws up more water via surface tension from further down and brings dissolved nutrients with it. The nutrients remain where the water turns into vapor and leaves the surface. None of this happens in a pot full of rocks.
Also, no mention is made of the possibility of nitrogen fixation by bacteria living around the roots. (However I did not read it intensively). The plants are getting their N from somewhere and it's not from solid rocks. Thunderstorms also play a part.
The phosphorus question. No one knows what the affect of too much P on cacti looks like. The only way to know is to do a trial with blocks of identical seedlings and give each block ever increasing concentrations of P. But it would probably turn out to be rather pointless because we already know that we should not give too much P from the results of other trials for other plants. So why do it in the first place? The trial for African violets showed flowering decreasing by 50% when the N/P ratio was increased from 0.14 to 0.44. If we stick to somewhere around 0.25 to 0.35 more or less, there will be no problems.
Last edited by MikeInOz on Sat Feb 18, 2023 1:12 am, edited 2 times in total.
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Re: The Cal-Mag of my dreams?

Post by MikeInOz »

jerrytheplater wrote: Fri Feb 17, 2023 1:03 am

It comes out at 9-3.6-13.5. I water at 50 ppm N.
Jerry,
Those ratios are close to perfect IMO. I wouldn't go any higher with the P however. Your next mission (should you choose to accept it) is to find a commercial off the shelf fertilizer with those ratios.
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Re: The Cal-Mag of my dreams?

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MikeInOz wrote: Sat Feb 18, 2023 12:42 amThe trial for African violets showed flowering decreasing by 50% when the N/P ratio was increased from 0.14 to 0.44. If we stick to somewhere around 0.25 to 0.35 more or less, there will be no problems.
Okay, then I do have a problem, although I don't think it's a big one...

Just to review, the Dyna-Gro 7-7-7 I've been using since 2012 has a true NPK value of 7-3.052-5.81. That gives us a ratio of -- 1-0.44-0.83. Oddly enough, flowering on a good number of my cacti actually increased when I added CalMag to my 7-7-7 and Potassium sulfate fertilizer regimen last year. With that said, I may have to get rid of the 7-7-7 in favor of a lower-P fert. I like Jerry's idea about the Foliage-Pro supplemented with Mono Potassium phosphate and Potassium sulfate, but I like your idea even better -- a commercial off-the-shelf fertilizer with the ratios he stated. My mother has been using an orchid fert which may be right up our respective alleys, powder form diluted in water. When I looked at its guaranteed analysis last year, I was impressed enough to recommend it for her succulents too. I'll be seeing her for dinner tomorrow, so I'll look at the guaranteed analysis on the label again and take a photo of it here for your considered opinion. If it's good enough to start using for my cacti, the 7-7-7 is done and gone.

Regarding your assessment of those Xerophilia articles, it confirms my suspicions about their usefulness (or lack thereof).
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Re: The Cal-Mag of my dreams?

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MikeInOz wrote: Sat Feb 18, 2023 12:42 am The phosphorus question. No one knows what the affect of too much P on cacti looks like. The only way to know is to do a trial with blocks of identical seedlings and give each block ever increasing concentrations of P. But it would probably turn out to be rather pointless because we already know that we should not give too much P from the results of other trials for other plants. So why do it in the first place?

The trial for African violets showed flowering decreasing by 50% when the N/P ratio was increased from 0.14 to 0.44. If we stick to somewhere around 0.25 to 0.35 more or less, there will be no problems. I didn't read that article and want to look at the information regarding African Violets. I have been using Dyna-Gro Bloom on my three African Violets for many years now. I do alternate with DG Grow every once in a while-no plan. I have to say my plants bloom almost year round.
I am still thinking of doing a trial using Frailea parviflora seedlings with increasing amounts of P. The one drawback is I will need room to grow these plants and store them over winter. I can see this taking a year or two. That will be a huge factor if I do this.

I calculated three fertilizer solutions using the Dyna-Gro Foliage-Pro. I'm attaching them, I hope it is readable. I tried to keep all the nutrients constant except P, but I had to boost S using Sodium Sulfate and this caused the sodium levels to be different in the three solutions I envision using. The middle one is the one I use already except for the boosted S.

Why do it? For me, it is to see how much P is too much. If all plants look the same after a season or two, then there is a start to know what are good commercial fertilizers besides Dyna-Gro.
Foliage-Pro experimental P level fertilizing.jpg
Foliage-Pro experimental P level fertilizing.jpg (161.07 KiB) Viewed 1777 times
Jerry Smith
Bloomingdale, NJ
45 inches (114 cm) rain equivalent per year, approx. evenly spread per month
2012 USDA Hardiness Zone 6b: -5F to OF (-20C to -18C) min.
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