Ca and Mg again

[Rick]

One thing that everyone except Xavier seems to ignore are the micronutrients.
Xavier (Roth) has repeatedly written that the Fe:Mn:Zn balance normally is more or less opposite to the chemistry of wild-grown leaves. You may find more on that in Xaviers thread on "Mineral Nutrition".
The reason why I mention this is that I noticed a growth spurt on my randsii seedlings once I sprayed with Dithane which is basically a manganese-zinc compound. Suddenly they started growing at the speed of normal paphs!

I haven't totally ignored the micros Bjorn, and this may get everybody all inflamed again, but K is antagonistic to Zn (probably just about all cations besides Ca and Mg).

So after taking the K out of the equation, I've been waiting for the last few years to see if other issues maybe related to micros will pop up. Not for me yet though.

 

[Stone]

I'm hurt Mike

Didn't you like my Maxilaria tenufolium

That's in a pot

And SlipperKing has been garnering a lot of awards with his plants (mostly in pots) since going low K.

Emydura has his own version of low K which seems to be producing some amazing results.

I don't think its the baskets for anything other than it reduces the overall exposure to fertilizer (like a mounted plant).

But my mounted plants have also improved. (Didn't you like my Phalae pallens?)

Didn't mean to hurt Rick!
What sticks in my mind more than any other was the the mastersianum and the delenatii. I can't remember all the plants you are posting but I am willing to take your word that they are all thriving. But it is very hard to compare yours with a thousand others and say this or that is doing better.
I also have lots of plants which I'm pretty proud of and which have won cultural certificates and have all been fed quite heavily with K. I wonder if with paphs at least, feeding very low consentrations is more important than worrying too much about the potassium ratio.

 

[Rick]

That there are countless examples of these orchids doing equally well with K concentrations as high as the N given to them.

However, from the countless complaints I see on this forum the old traditional fert applications aren't cutting it. (or orchid growers are perpetual whiners). Your countless examples really seem to be in the minority.
Then when an alternative to the system is suggested then everyone is in denial of their complaints:sob: And we start dragging out those pics of the one plant (out of 100) that turned into that awesome specimen plant that got the CCE (forgetting the pile we just put into the compost heap).


The traditional agri food crop application methods produce orchids that emulate expectations for food crops. Lots of production in short time frames requiring lots of labor and material effort followed by trash can. I would guess that the bulk of orchid growers are just fine with that, and are encouraged to be fine with that attitude. Hybrid Phalaes have replaced poinsettia as the ultimate throw away plant.

And the agri science folk pace nutrient load based on soil deficiencies and plant age. The orchid hobbyists modus operandi is to apply the kitchen sink in mass quantities regardless of the age of plant and then scratch there heads wondering how the corn farmers do it so easily?

I responded to complaints and perceived inadequacies in my growing by breaking out of the "how everyone else does it" system and looked for a common solution, instead of the myriad of excuses and grasping at minutia that orchid growers seem to get fixated on.

And so far its still working

 

[Stone]

However, from the countless complaints I see on this forum the old traditional fert applications aren't cutting it.

It would be nice if the biggest limiting factor was fertilizer, but sadly it's not. Most people who fail with orchids have not had the experience (or the time) to learn how not to kill them.

Just using the wrong mix or not noticing when a plant needs repoting or overwatering can quickly (or slowly) kill it. Yes adding fertilizer just makes it die more quickly but it's not the cause. The cause is not noticing something is wrong in time.

If I see any plant producing new growths smaller than the previous I know that there is a problem with the roots every time! Others might see the same thing and feed more and/or water more the with the result being that the orchid just gets worse.

Thats how plants are killed not because of too much potassium IMO.

Why is there problem with the roots? I beleive its wrong watering technique.
We are all doing it...watering a huge mixed collection of species the same way and the same time. It's natural that sooner or later a plant here and there will succumb to treatment they are not able to handle.

Your countless examples really seem to be in the minority.

On the contrary, I think they are in the in VAST majority. How many growers are there around the world with vast collections thriving as well or better than in the habitat? Must be in the millions. None are using low potassium! The really good growers are probably in their greenhouses most of the day treating each plant individually.

 

[DarioU]

Perhaps I tend to simplify but if the problem would be that K blocks the uptake of Ca and Mg could we superate the problem giving these elements not mixed in the same time? One time NPK fert and an other day Ca/Mg fert.

 

[Rick]

DarioU

It depends on the type of potting mix, the frequency and amount of application, and the concentration applied.

High Cation Exchange of various potting mixes will hold up K rather than Ca/Mg. It's not just a basic sponge effect, but a chemical bias. And once its in the mix it takes a high dose of Ca or Mg to knock it back out. What you suggest probably is happening for lots of growers when they fertilize with NPK infrequently and water frequently with are regular city or well water that has plenty of Ca/Mg in it already.

Orchiata bark prides itself on having a low CEC so it holds up less K over repeated fert applications. You might have seen reference to Xavier who supplied data to this site showing that Orchiata holds up less than 1/2 the potassium compared to coconut coir and sphagnum moss.

Lots of folk are having good results using Orchiata bark (which was lime composted). You probably don't need to add any separate Ca/Mg using this material and if you mix your standard NPK fert in diluted city/well water you will also get a lot of Ca Mg without having to add it in from separate components.

Do you have a water report for your drinking water?

You mentioned high sodium, but it is rare that well waters are higher in Na than Ca unless they have been run through a water softening system.

I also have well water that has very high EC but it is all salts of Ca/Mg with low Na. I dilute it 10 or 20:1 to add Ca/Mg

 

[DarioU]

Thank you Rick. My well water (not tap water) has 68 ppm Ca, 21,9 ppm of Mg and 36,2 ppm of Na. Because I have read that Na has to be lower then 10 ppm and better lower then 5 ppm I diluite Well Water/RO water 1:4.
What do you think about it?
Dario

 

[Rick]

http://cpl.usu.edu/files/publications/factsheet/pub__9468201.pdf

DarioU this kind of goes back to your original question.

addition of gypsum didn't help out with the high K coir

 

[Stone]

the old traditional fert applications aren't cutting it

Rick, Can I remind you of the magnificent example of P. bellatulum posted by e-spice a while back. One of the best and healthiest I've ever seen and one we all aspire to I would think!
The fertilizer used. MSU...and from memory MSU has a very high K/N ratio.
Ouote " I use a very dilute MSU (from Ray's) and some Mg now and then''. (It was grown in semi hydro)
Surley this puts to to rest the notion that you can't use high K fertilizers (for whatever reason)? So if you use less K for high CEC media, and keep it (the solution) well diluted (for paphs or brachys at least?), there will be no problems with Ca absorbtion or anything else.
Go back and look at the plant and tell me what you think.

 

[Rick]

Rick, Can I remind you of the magnificent example of P. bellatulum posted by e-spice a while back. One of the best and healthiest I've ever seen and one we all aspire to I would think!

Well that's one blast from the past Mike, so now show me where that plant became just one of the "vast majority" of bellatulum out their in culture. I also grew a bellatulum to that size with MSU. Repotting every 6 months, loosing all the roots/regrowing roots, bag n'sphag, adding oyster shell, ...... when it got up to 8-10+ growths it started producing stunted growths (though still blooming). I switched it over to SH as per ESpices example, it frittered away to nothing. I went through a whole compot of seedlings from a selfing of this plant. All 25 are gone after trying all the usual ascribed methods and materials (including SH). None even made it to a first blooming. The common thread was MSU at 100ppm N weekly.

So why didn't MSU SH work for my bellatulum? I truly tried to apply what I learned from Espices fantastic plant.

Why isn't every GH filled with monster pots of bellatulum when literally thousands of seedlings are sold each year?

Espices awesome plant was something we all aspired to because no one else was achieving that result. It wasn't in the "vast majority" of bellatulum in culture.

That was also a few years ago, so it would be good to get an update on that plant.

I've also had lots of big, impressive, enviable plants grown on MSU at high feed rates that are no longer around. I'm not saying it can't be done, I'm saying its not worth the effort and loss to get there. In developing the low K system I was primarily responding to all the complaints of species that "cannot be grown in artificial culture". I didn't suspect it would make such a difference for all my easy stuff.

 

[Rick]

Rick, Can I remind you of the magnificent example of P. bellatulum posted by e-spice a while back. One of the best and healthiest I've ever seen and one we all aspire to I would think!
The fertilizer used. MSU...and from memory MSU has a very high K/N ratio.
Ouote " I use a very dilute MSU (from Ray's) and some Mg now and then''. (It was grown in semi hydro)

http://www.slippertalk.com/forum/showthread.php?t=13111

Interesting history from 2009.

I can't recall how "very dilute MSU" was for E-spice at that time (could have been down to around 10-20ppm N and therefore K around the same concentration", but apparently that didn't translate to success for barbata types.

Also note that in 2009 Ray was pretty happy with MSU at 125ppm N (~135ppmK), but got happier with K lite at 35ppm N (~3.5ppm K) in 2012/2013.

 

[DavidCampen]

http://cpl.usu.edu/files/publications/factsheet/pub__9468201.pdf

addition of gypsum didn't help out with the high K coir

Because the potassium content of the coir was not causing a calcium deficiency. The authors state that they were unable to determine the cause of poor growth in coir. The only take away from this article is to not use coir. The article says nothing that supports your potassium toxicity conjecture.

In the introduction of the article there is mention of another publication that claimed that high potassium content of coir available in Australia required the addition of gypsum to increase calcium uptake but the experimental data in the article does not support this.

 

[Stone]

.

I also grew a bellatulum to that size with MSU. Repotting every 6 months

Well there's your problem Repotting these things can set them back 2 years! (CAN!)

The common thread was MSU at 100ppm N weekly.

Yes this may be part of the problem. Assuming all other aspects of the culture are perfect, and depending on media composition and salt build up it may very well be that 100ppm is still way too high for some of these plants. And even at very low concentrations, it is possible that salt build up could still easily occure without a very thourough flushing now and then to bring the media EC right back down to 0 ar close to it.
Judging from espice's plant I would guess that the perfect balance between uptake and application was achieved probably helped by the fact the roots remained constantly wet which would avoid the wild swings in EC caused by the usual wet/dry cycle.
So perhaps the moisture content of the substrate is vitally important when you are applying fertilizer. Or conversly, the consentration of the nutrient solution is very impotant when you are growing with the conventional wet/dry method.

It wasn't in the "vast majority" of bellatulum in culture.

Very true (see above for my suggestions why) But obviously nothing to do with low K here but possibly everything to do with low/ stable EC (along with all the other growing parameters of course.

That was also a few years ago, so it would be good to get an update on that plant.

I've also had lots of big, impressive, enviable plants grown on MSU at high feed rates that are no longer around.

Again, high rates is not the same as high K ratio

 

[Stone]

I can't recall how "very dilute MSU" was for E-spice at that time (could have been down to around 10-20ppm N and therefore K around the same concentration", but apparently that didn't translate to success for barbata types.

Not sure what concentration was used. I'm finding it easier to grow my brachy seedlings than barbatas. Why I still don't know. Possibly a humidity issue? But I would suspect that barbatas coming from a more ''leafy'' and dense forested habitat may have more K available to them than something from a limestone cliff?

 

[Rick]

Because the potassium content of the coir was not causing a calcium deficiency. The authors state that they were unable to determine the cause of poor growth in coir. The only take away from this article is to not use coir. The article says nothing that supports your potassium toxicity conjecture.

In the introduction of the article there is mention of another publication that claimed that high potassium content of coir available in Australia required the addition of gypsum to increase calcium uptake but the experimental data in the article does not support this.

I didn't claim that this article supported the position that potassium blocks K, just that adding Ca did nothing to increase Ca in the plants.

 

[Rick]

Because the potassium content of the coir was not causing a calcium deficiency. The authors state that they were unable to determine the cause of poor growth in coir. The only take away from this article is to not use coir. The article says nothing that supports your potassium toxicity conjecture.

The GrowCoir did really good compared to the Peat control.

The sufficiency standards for corn from MSU indicate leaf K should be between 1.6 -2.5% and Ca 0.2-0.8%

The Tropic grow coir ended up with 3.7% K and 0.3% Ca (regardless of Ca added to the pot). By MSU standards that plant wouldn't be experiencing Ca deficiency, but outright K toxicity (MSU's words not mine). I would acknowledge that some trace nutrients are also elevated, but I don't have the sufficiency standards handy for them. I guess you can blame the poor results on toxicity of those metals if you don't agree with the K sufficiency standards established for corn.

The GrowCoir corn did great (regardless of Ca added to pot). Those plants ended up with only 1.79% K and and 0.28 Ca. Both values within published sufficiency standards and healthy looking plants to corroborate.

Another take home point from the article would also appear that adding Ca doesn't reduce K in leaves.

 

[Rick]

Thank you Rick. My well water (not tap water) has 68 ppm Ca, 21,9 ppm of Mg and 36,2 ppm of Na. Because I have read that Na has to be lower then 10 ppm and better lower then 5 ppm I diluite Well Water/RO water 1:4.
What do you think about it?
Dario

That works for me Dario

Do you have the other major ions ( sulfate, chloride, bicarbonate and potassium) values for your well water?

 

[DarioU]

Cl 60,1 mg/l; SO4 61,6 mg/l; K 0,8 mg/l; Zn 12,3 microgr/l; Mn 52,2 microgr/l; Durezza 26 F°; EC 442 microSiemens/cm.
My well water works diluite 1:4 in RO water or without any diluition?
Na is not too hight?
In the web site of St. Augustine Orchid Society I have read that Na must be lower then 10 ppm.
Thank you
Dario

 

[gonewild]

All very interesting Lance and thank you. However it tells me nothing about what and how I should feed my orchids. Only that they get low concentrations of everything which we already knew.

You don't see that the nutrients are not moving through the moss in stem flow?

Based on my sample tests it is obvious that the majority of nutrients are supplied by organisms within the root zone and not rain water or atmospheric dust particles.

It tells me a lot about what you should feed your orchids.
The concentrations are not that low in reality and only dissolved salts are measured. But clearly there is not much potassium flowing freely from the canopy as you maintain.

Potassium probably has a toxic effect on all the micro organisms within the root zone. Applying fertilizer levels with K above the toxicity level for the nutrient providing organisms will throw the entire nutrient supply out of balance. The more toxic you keep your growing media the more nutrients you have to apply and the more you take the nutrient supply away from a correct ratio of balance.

How this pertains to the Ca/Mg availability I have no idea but it does seem to have a big effect. It's time for Horticulture to realize that plants don't only utilize NPKCaMgFe from dissolved free flowing salts. The velum of the orchid root should be alive with LIVING nutrient producing micro organisms providing nutrients in many chemical forms such as amino acids and compounds not detected. Does potassium kill these organisms?
K-lite indicates it does (at least to me it does).

I just returned from several days up in the cloud forest, plenty of clouds but zero water fell from the sky, not as rain or fog. But the moss and orchid roots are wet with local moisture and the plants are growing. Growing from nutrients supplied by the living moss/lichen fauna.

 

[Stone]

You don't see that the nutrients are not moving through the moss in stem flow?
To me all the your samples represent ''free'' nutrients.