low potassium concept is not sustained by analysis

[Rick]

So why waste all that fert if none of it makes a difference?

If we can grow great plants with and without hundreds of ppm of K then why should we waste time/money digging it out of the ground and spraying our plants with it?

 

[Brabantia]

I agree that the "suddenly paying attention aspect" is fairly common in the introduction of almost anything. The casual grower can get pretty complacent, with many cultural aspects slipping, but then with the addition of something new, that interest level is rekindled, and ity's amazing what happens!

I remember that the same situation was occurring when the MSU was introduced. Same with the AKERN RainMix here in Belgium.

 

[gonewild]

So far, to make a reply over the whole thread:


The easiest way for some people to test would be to add ammonium nitrate to the K Lite and see how the plants performs after that. I am certain that they would grow tremendously better ( and not soft or forced after that...). Several people on the forum already reported so, with the use of urea or ammonium and a K Lite variation home made... Some others reported the same with MSU and ammonium added too.

I don't disagree or agree with the addition of ammonium or increasing the K ratio. The low potassium concept using K-lite is still in the ongoing public trial phase. So far no one has reported negative results that proved to be due to low potassium levels. In fact the observations to date have all been positive. Based on the reported observations there is no reason to think the potassium ratio should be increased.

I don't think anyone thinks that the ratios or formulation in K-lite is exactly perfect. So far the formulation for most growers is working well. If people start making changes at this point when no problems are evident the end result will be nothing learned. If and when problems arise that is the time to evaluate the problems and devise a solution.

What I do disagree with is your thread title here implies that the Besgrow trials prove that the "low potassium concept" is not correct.
The trial really has nothing to do with the relationship between fertilizer and plant nutrition since it was designed and performed with growing media as the focus. The trial did not even utilize a low potassium ratio fertilizer. What I see in the trial results that you have presented is evidence that soil media affects the amount of nutrients the plant has available and nothing that is valid to look at potassium "toxicity".

I seem to remember that when we discussed the use of ammonium in the K-lite formula and there were logistic reasons not to use it. Trying to include ammonium made it difficult to get all the ratios at desired levels and have the dry fertilizer be stable in a single package. If a growers pH is not correct for an all Nitrate fertilizer it is pretty simple to add ammonium at the time the fertilizer is mixed.

So give advice about adding ammonium but don't discredit the "low potassium concept" based on these trial results.

FYI... I appreciate your input and the chance to debate it. I also have no problem with your connection to the company selling the products you discuss.

 

[gonewild]

So why waste all that fert if none of it makes a difference?

If we can grow great plants with and without hundreds of ppm of K then why should we waste time/money digging it out of the ground and spraying our plants with it?

Or send it out in waste water to pollute the waterways and kill the mussels and microorganisms that do help plants grow?

 

[naoki]

So far, to make a reply over the whole thread:

- The results would be that people must not be afraid of potassium as an evil evenement, and the low K benefit lies mostly in a problem due to the use of an all nitrate fertilizer. In fact we found that the all nitrate fertilizer does not perform well at all. I cannot disclose more, because some are our customers for pot plant, including non phalaenopsis and quite fragile plants ( miltoniopsis), but indeed they tried nitrate as a source of nitrogen, with Orchiata, with NZ Sphagnum moss, even with coir, and even with mixes not related to Besgrow. I advised them all, and they are really huge nurseries, some of the biggest even. Their problems vanished as soon as they added ammonium. Strong, long lasting plants.

The potassium levels in our study were about half the ones of Cornell ( what the hell did they use ???), and this shows even further than potassium is not toxic through accumulation. It could be that, using a nitrate nitrogen fertilizer, a problem appears due to the potassium, but on a general sense, there is no problem.

It's interesting that the results of NH4 vs NO3 is a sharp contrast to a paper published in a peer reviewed journal. We discussed this and paphs could be different from phals, but I wonder why you get a complete opposite result from Wang (2008). It's difficult to evaluate the results until the paper is published, but maybe K concentration differed, and resulted in the contrast?

http://hortsci.ashspublications.org/content/43/2/350.short

Also, what is the physiological reason behind the NO3-K interaction? I haven't seen any published study, but again epiphytes could be different.

 

[Rick]

In our study too, the plants with the lower K content had higher contents of sodium and lithium... so it seems that those three guys can be interchanged. Maybe Rick low K pushes more sodium in the plant ( this is not detrimental, plants need sodium anyway... and plants can be deficient in sodium clearly), or??? But definitely not a K toxicity problem per se.

It is well known in plant physiology circles that K and Na uptake are competitive. But what cracks me up is that as long as I've been growing orchids Na has always been considered "evil" and too be avoided at all costs. Now all of a sudden its a necessary nutrientoke:oke:

In the environment Na is way more common than K. The low K system, or my personal growing practices didn't add any Na to the system to address that. So if our plants were suffering from Na deficiency then once again excess K is a culprit for causing that.

 

[gonewild]

It is well known in plant physiology circles that K and Na uptake are competitive. But what cracks me up is that as long as I've been growing orchids Na has always been considered "evil" and too be avoided at all costs. Now all of a sudden its a necessary nutrientoke:oke:

In the environment Na is way more common than K. The low K system, or my personal growing practices didn't add any Na to the system to address that. So if our plants were suffering from Na deficiency then once again excess K is a culprit for causing that.

Rick your plants do suffer from a serious lack of Sodium. You just don't recognize the deficiency symptoms...... Plants deficient in Sodium have green leaf tips. :evil:

 

[Rick]

The potassium levels in our study were about half the ones of Cornell ( what the hell did they use ???), and this shows even further than potassium is not toxic through accumulation. It could be that, using a nitrate nitrogen fertilizer, a problem appears due to the potassium, but on a general sense, there is no problem.

You should read the study. They used raw chemicals not a commercial formulation (that's the only way they were able to increase/decrease different parameters).

Also growth inhibition is a generally accepted determinant of toxicity (which they did observe at different concentrations per species per parameter.

They did not see acute toxicity (mortality), but did see differing rates of growth under different regimes.

 

[Rick]

Rick your plants do suffer from a serious lack of Sodium. You just don't recognize the deficiency symptoms...... Plants deficient in Sodium have green leaf tips. :evil:

OH NO!!!! Where's the salt shaker!!!

 

[Rick]

Also, what is the physiological reason behind the NO3-K interaction? I haven't seen any published study, but again epiphytes could be different.

Naoki I thought I sent a link on K inhibition to photosynthesis (in BG algae). (Maybe a couple of other links on how the photosynthesis II system works)

K piling up in chloroplasts seems to increase cellular alkalinity levels dramatically(decreasing the efficiency of photosynthesis) The nitrate reductase system is part of the Photosynthesis II system (which is part of all photosynthetic plants physiology). If you cut down photosynthetic efficiency, you also retard the plants ability to convert nitrate to ammonia. Also high levels of intracellular alkalinity (bicarbonate ion) make nitrate uptake from the root zone and uphill battle if there is high alkalinity in the root zone.

Since the plant uses NO3 to make NH3 to make amino acids, then you can see you can sidestep the whole NO3 issue by going direct to NH3 or amino acids.

The next "however" is pot management of ammonia usage. Yes a more direct use by plants, but also causes more problems with pH and microbial management. Nitrate causes less pot management issues (pH or microbial).

 

[gonewild]

I did a little goggleing on Phalaenopsis.

http://www.ranwild.org/Phalaenopsis/Eindex.html

After reading this well written site on Phalaenopsis species it is obvious that Phal hybrids are not a good choice to use for nutrient trials. Phal species have a very wide range of environmental requirements and now the hybrids have a mixed up genetic makeup of species with very different growing requirements. Phal hybrids do not represent the requirements of general orchid plants as found in a mixed collection.

As complete as this website is it offers very little about specific nutrient requirements of Phals but it does say the nutrient requirements are low. It does mention Nitrogen and Phosphorous but not potassium.

Nutrient trials using Phalaenopsis plants will lead to growing better commercial crops but may very well mislead growers of species and other genera.

 

[Ray]

Ray,

Did you continue to water with the same TDS as before you changed to K-lt.? If so, by decreasing the P & K isn't that, in effect, the same thing as increasing N and keeping the TDS the same as before?

Not the same TDS, the same nitrogen loading, so the TDS will be lower.


Ray Barkalow
Sent using Tapatalk

 

[Stone]

Mike, I'm still not convinced it's necessary, either, but I think that proving - or disproving - the concept is a very long-term thing, and none of the data shown is of a long-enough term to tell us anything, making these debates rather senseless.

I don't know how long term it really needs to be. 2 growing cycles should be enough to show any trends to my mind. However because there does not seem to be any extrodrinary difference between what Rick has shown and what other good growers show using more conventional ferts, I tend to agree that these debates are a bit sensless given that we really don't know exactly what the hell is going on in the pot. Maybe the plants have a way of adjusting there root evironment to suit themselves? We don't really know how much added NH4 is being converted to N03, we don't really know if N03 is being efficiently converted in the roots or the leaves, we don't really know if the plants on low K are replacing it with Na. But we do know that you can grow very nice plants long term with ''normal'' K. Just look at the insigne on the Specimen thread, I know for a fact that it is being fed with organic pellets which have ammonium sulphate added to boost the N and a similar amount of KS04! So I would call 20 or so years pretty long term. Not too high an EC and tons of water are the ''sectrets'' Here is what he uses, I don't like it much, I think there are much better alternatives but look at the K!
http://www.neutrog.com.au/assets/Brochure-PDFs/Home-Garden-PDFs/NEU-SBFO-0812.pdf

 

[gonewild]

Just look at the insigne on the Specimen thread, I know for a fact that it is being fed with organic pellets which have ammonium sulphate added to boost the N and a similar amount of KS04! So I would call 20 or so years pretty long term. Not too high an EC and tons of water are the ''sectrets'' Here is what he uses, I don't like it much, I think there are much better alternatives but look at the K!
http://www.neutrog.com.au/assets/Brochure-PDFs/Home-Garden-PDFs/NEU-SBFO-0812.pdf

This is copied from the front page of the link to Strike Back fertilizer.

"Neutrog commenced development of Strike Back for Orchids in early 2006"

Can't really credit this fertilizer formula with 20 years of specimen plant growth.

 

[gonewild]

I don't like it much, I think there are much better alternatives but look at the K!
http://www.neutrog.com.au/assets/Brochure-PDFs/Home-Garden-PDFs/NEU-SBFO-0812.pdf

Thanks for this link. I have never heard of this fertilizer before so I'm reading it. You are correct the K ratio is high. But note they do not recommend it's use on small plants as the formula may damage them. Instead they recommend their "Seamungus" fertilizer which is:

Nitrogen (N) as Organic 4.0
Phosphorus (P) as Citrate Soluble 1.0
Potassium (K) as Organic 1.5

Now look at the K!

 

[Stone]

Thanks for this link. I have never heard of this fertilizer before so I'm reading it. You are correct the K ratio is high. But note they do not recommend it's use on small plants as the formula may damage them. Instead they recommend their "Seamungus" fertilizer which is:

Nitrogen (N) as Organic 4.0
Phosphorus (P) as Citrate Soluble 1.0
Potassium (K) as Organic 1.5

Now look at the K!

Yes the ammonium content can damage very tender plants especially in cold dark weather, nothing to do with the Koke:

 

[Stone]

This is copied from the front page of the link to Strike Back fertilizer.

"Neutrog commenced development of Strike Back for Orchids in early 2006"

Can't really credit this fertilizer formula with 20 years of specimen plant growth.

Ok 7 years then.

 

[gonewild]

Yes the ammonium content can damage very tender plants especially in cold dark weather, nothing to do with the Koke:

Then why do the drastically lower the K in the other recommended fertilizer? oke:

 

[gonewild]

Ok 7 years then.

So what fertilizer did he use to grow it to specimen size for the 30 prior years?

Just think how big it would be now if he used low K. :clap:

 

[Stone]

So what fertilizer did he use to grow it to specimen size for the 30 prior years?

Send me some kovachii seed and I'll tell you