K-Lite Testers: What do you grow, and have you made any observations?

[SlipperFan]

That was an interesting survey of fertilizer history, Leo. I wonder if you or someone could address the adage "Weakly weekly" in that light. My unscientific opinion is that it doesn't hold for contemporary fertilizers like MSU or K-lite, and that the recommended doses should be a fairly good guideline for application.

 

[Rick]

I wonder if you or someone could address the adage "Weakly weekly" in that light. My unscientific opinion is that it doesn't hold for contemporary fertilizers like MSU or K-lite, and that the recommended doses should be a fairly good guideline for application.

From the poking around in looking at the development of the contemporary fertilizers, "weakly weekly" is a pragmatic adaptation to the observation that standard heavy doses of basic balanced fertilizers were killing orchids. Going back into the history of horticulture, plant "feeding" was started for the development of food crops, with the goal to produce the most high calorie edible product in the least amount of time.

Food crops are highly selected domesticated species. Generational time is about 1 year compared to 5-10 years for orchids (if you push). The priority to maximize food production is way beyond the need to maximize production of ornamental crops. So plant research and nutrition in the food crop area is light years ahead of ornamental plant research. Then if you look into things like nutrient flux in rain forests, no body got serious about that till the 1950's when the worlds population wanted to replace all the rainforests with farms (still the priority on food crops).

Before MSU, orchid growers were adapting applications for more common indoor/outdoor ornamentals, which were adapted from crop production feeding regimes. And by observation, figured out that orchids just can't keep up with corn. These observations (complaints) are just about the same ones I brought up when thinking of K lite, but more frequent, obvious, and severe. Weakly weekly was how orchid people with the "difficult plants" got them to hold up.

MSU formula was really cutting edge by looking at leaf tissue data for direct application to ornamental plant requirements. But it came out of the culture of the annual cut flower world and greenhouse/hybrid orchid venue. Still a fair amount of genetic selection involved, and a push for fast growth return.

K lite just takes this a notch farther by leaning more on species data, in situ jungle leaf tissue data, and physiology data from epiphytic species.

 

[Leo Schordje]

Thanks Rick. Just so it is here, could your go over briefly what I should be doing if I use city water, at roughly 225 to 250 ppm TDS assume 175 or so ppm as Calcium Carbonate?

If you think I should add a little ammonium to the continuous fertilizing K-Lite regime while using city water, how would household ammonia from the local grocery store work as a source of ammonium ions? Since I want to max out at about 70 ppm N, and the bulk will be from the K-Lite, would it be a good alternative source. What do you think. Or should I find a source of ammonium nitrate. I no longer work at a Chem Manufacturer, so getting shipped to me might be a problem. (Homeland Insecurity, etc) For those that don't know, ammonium nitrate can be used in primitive home made explosives.

That was an interesting survey of fertilizer history, Leo. I wonder if you or someone could address the adage "Weakly weekly" in that light. My unscientific opinion is that it doesn't hold for contemporary fertilizers like MSU or K-lite, and that the recommended doses should be a fairly good guideline for application.

Hi Dot,
Rick is dead on, weakly weekly, with clear water in between was a work around for my orchids. I forgot where I first heard it, definitely the low dose, 1/8 to 1/4 teaspoon per gallon for a 30-10-10 fertilizer was to compensate for the damage the excess phosphorous and potassium was doing to the plants. But it is weakly weekly that inspired my first forays into continuous feeding. One merged with the other.

 

[Stone]

to compensate for the damage the excess phosphorous and potassium was doing to the plants.

I see no evidence of standard potassium levels damaging my orchids. Where is the damage? What should I be looking for? I'm using 16-4-9 or something like that on everything and so far I've never had better growth and flowering. It still seems to me that as long as there are no gross imbalances, that Ca is higher than Mg and that K is not too high during the growth season and the overall level of nutrients is low to very low, the plants find what they need regardless of what we do. Don't get the idea that K is evil, on the contrary, it can have many positives. For instance, a dose of K along with reducing N during the slow-down period in the fall/winter will help ''toughen'' plants up for the cold season. In fact I'm almost certain that giving your plants a very low K diet along with a mainly inert media with very low CEC will eventually lead to trouble. It has to! IMO k-lite should be used only with media containing lots of moss or chc or peat. ONLY MY opinion!! CEC of bark is pretty low until it starts to humify by which time we usually throw it out.

 

[The Mutant]

After figuring out your units for conductivity, this water is soflt and low salt. Adding sodium hydroxide (caustic) is a fast way to raise pH, but my be pushing the alkalinity up. Try letting the water stand or aerate with an aquarium pump for a day or so and see if the pH drops.

You shouldn't need to add the crushed oyster shell or other lime products when using K lite.

Given the very short time frames over which you are seeing problems, I think you have something more fundamental in your culture going on. Temp fluctuations, low humidity, and/or lighting limitations.

I've tried to see if I can find any testing kits for water quality here in Sweden, but no luck so far. I have, however, found some on amazon.uk, I hope they deliver to Sweden.

Oh, I didn't know that, no crushed oyster shell, that's good. One thing less to think about.

I always let the water stand at least 24 hours before using it. Problem is, I can only do this with 2 liters at a time, so that water always go to the species I figure are more sensitive (my Phrag, my violascens, etc.). BUT, this is important, I have found out where to get RO-water! So I'm going to buy as much as I can afford to and start mixing it with my tap water. This should help a bit I hope.

Yes, I think you're right, and that it's some sort of lighting limitation and humidity issue. I'll see what me and my wallet can do to ease the problems some. I don't know which of the problems to address first though, light or humidity?

Again, thank you so very much for your help and thoughts. It means a lot to me.

 

[Ray]

Just a comment or two on "recommended" rates of application:

► Dave Neal, president of Dyna-Gro (or was; I haven't spoken to him in years) was a big believer in very dilute application of fertilizer. He once told me that he thought it encouraged the plants to grow more roots in an effort to find more nutrition. I went with about 30 ppm N of his "Grow" formula (7-9-5) at his recommendation for about 10 years, and was quite happy.

► A few months ago, in a discussion with Bill Argo, he brought up the 125 ppm N level they used in the MSU study, and said "You know how we came up with that? We tried it and it worked. No scientific thinking or any analysis was used.", and he acknowledged that it may be "great" or "way off" of the true needs of the plants. That 125 ppm N is the recommended level I list on the labels when I repackage the stuff, but it's stronger than I use.

► I just reordered some product from Bill, and he and I had a fairly lengthy chat about plant nutrition, mostly so I could update him on what we've observed - or had not observed, like deficiencies, which may be even more important. My take is that he thinks we might be in for a rude awakening some day in the future, but he acknowledged that nobody really knows what goes on within the plant when it comes to nutritional formulas and uptake. Analytical techniques have improved and may help with that, but plant tissue analyses and sampling of the environment only paint a very limited picture, so to me, experimentation like we're doing is the way to go.

 

[Rick]

I must say that I see NO evidence of standard potassium levels damaging my orchids. I'm using 16-4-9 or something like that on everything and so far I've never had better growth, leaf colour and flowering.

What is a "standard" potassium level Mike? MSU isn't what I would call a standard compared to the old "balanced" formulas like 20-20-20. But it has more K than N, Ca, Mg.

I would not call your material "standard" and K lite is not devoid of all K either.

There are lots of variables involved in this which you haven't accounted for. What is the chemistry of your irrigation water? How much Ca/Mg are available in it, the potting mix, and any extra potting amendments? What is the dose rate of your fert application.

I did a work around with MSU (cutting it with calcium nitrate and epsom salts) for about a year before going to K lite, and have already gone through at least one winter on low K. My general results have never been better.

If you look up the old threads when I started all this, I never mentioned acute destruction of plants as being a symptom of the levels of K typically used at the time. I was generally addressing poor growth, chronic disease, and poor long term results (the boom and bust syndrome). Short term problems revolved around poor growth and high mortality of seedlings in compot.

And I can remember your earliest posts on the site that were all complaints about certain plants, or groups of plants. So are you doing the same thing you did 10 years ago, and now is it better than ever?

You definitely have a large collection of long term awesome plants. So I don't always understand where you're coming from when you mention problems in your culture, and then discount any proposed solutions.

 

[Rick]

In fact I'm almost certain that giving your plants a very low K diet along with a mainly inert media with very low CEC will eventually lead to trouble. It has to!

About a 1/3 of my collection is mounted on plaques or in baskets with no media at all. I've already gone through a winter and they just keep getting better all the time.

What is "very low K". Put a concentration value to it, or mass per unit time.

If you feed K lite at 100 ppm N then you still get about 8ppm of K. That's still a lot higher than what plants in the canopy see during a massive rain event.

I have a compot of callosum seedlings that are in a leaf litter mix. They are growing great for about a year now, and I haven't fertilized them at all (just straight low EC water). I also potted up a blooming size Liparis in the same leaf litter media, and its putting up all kinds of new growth over the last year. Also no fert at all.

I still see the little old lady in Shelbyville, TN with 5 GH's of orchids. Some there since the 1950's. No chemical fert added whatsoever.

I don't think anyone is going to starve their plants on K lite.

 

[keithrs]

I agree that one is not going to starve their plants but that's not to say that will not see deficiencies at some point. We may see no deficiencies at all.

 

[Ray]

The jury is still out in my mind, too.

 

[keithrs]

I'm wondering how many of us are using kelp? I'm wondering if the person in FL is using it also? Being that it supplies some where in the realm of 70 vitamins and nutrients. Could be masking deficiencies in the k-lite program?

I'm probably the only one using fulvic acid and on the rare occasion humic acid.

I think if where going to see any true deficiency in the plants its going to be in the spring. (At least for the ones getting a winter rest) No fertilizer for 4-5 months then spring growth kicks in......Will see.....

 

[Rick]

I agree that one is not going to starve their plants but that's not to say that will not see deficiencies at some point. We may see no deficiencies at all.

However, these wouldn't be deficiencies caused by lack of resource as opposed to antagonistic deficiences caused by excess of a resource.

 

[Rick]

Being that it supplies some where in the realm of 70 vitamins and nutrients. Could be masking deficiencies in the k-lite program?

Micro nutrients. Of which most of the important inorganic materials are in MSU or K lite.

I believe lots of users of either MSU or K lite are not using kelp so not benifiting from the organic micro nutrients or vitamins.

 

[Rick]

I'm wondering how many of us are using kelp? I'm wondering if the person in FL is using it also? Being that it supplies some where in the realm of 70 vitamins and nutrients. Could be masking deficiencies in the k-lite program?

I'm probably the only one using fulvic acid and on the rare occasion humic acid.

I think if where going to see any true deficiency in the plants its going to be in the spring. (At least for the ones getting a winter rest) No fertilizer for 4-5 months then spring growth kicks in......Will see.....

If you remember one of the threads started by Chris in Florida, with his terrarium system. He doesn't fertilize/supplement at all and posted rainfall data (going back to natural levels of nutrient availability) indicating that deficiences from lack of fertilizing are really a fantasy.

Perenial plants growing in the wild do just fine at nutrient levels a fraction of what we pour on our plants. I never fertilize the plants/trees/ shrubs on my property nor the woods across the street (which I don't water either). And they seem to do just fine without truckloads of fertilizer being dumped on them.

 

[Stone]

What is a "standard" potassium level Mike?

The standard K to N ratio in coated fertilizers here is between (very roughly) .4:1 to.8:1 sometimes as high as 1:1 or more. So I guess somewhere in between these figures I would consider average. I'm sure it would be similar everywhere else.
So for aruments sake, lets say .5:1 or potassium at half the nitrogen levels. The osomocote formulation I'm using on all potted orchids at the moment is:
16.6-2-6.6+2%Mg. No Ca so I sprinkle course Gypsum crystals for the Calcium and that's it--once per year. with the paphs, Pillip,roth,exul, are getting the same. All the others (paphs) get Miracle grow ''Max Feed'' :20N - 2.2P - 9K - 5%Ca -.5%Mg. (The lowest in K I could find) mixed at 0.2 dSm then I add various organic preps to bring the EC to 0.3 dSm. The mounted stuff get the same but EC is double or more.
I also use kelp now and then (4%K)
I'm not sure how much K the original MSU had but from what I remember it had K at more than 100% of the N? That's much like your standard hydroponic mixes with I used to use before I moved here 4 years ago. The water there was very hard. It left terrible lime deposits on all the leaves, pH was 10 at times.
So maybe my fert at the moment is on the lower side of standard but still plenty of K. I don't know the Ca an Mg content of my water but I would guess it is low. The mains water is slightly acidic. EC is 0. For the paphs I use 50/50 rain/town water.

I was generally addressing poor growth, chronic disease, and poor long term results (the boom and bust syndrome). Short term problems revolved around poor growth and high mortality of seedlings in compot.

I find that when I have these problems (and everyone does) It's usually caused by neglect of some kind. The fact that we try to grow orchids from so many different climates and habitats in one area with the same techniques we're always going to have problems. When I see the boom and bust thing Its always caused by deterioration of the p/media. The substrate begins to decompose and it takes the roots with it. You wont see that happening in a plant thats growing faster than the media deteriorates. It seems to consume whatever is being decomosed and stays healthy. Thats why its easier to manage a large plant in a small pot than a small plant in a large pot.

And I can remember your earliest posts on the site that were all complaints about certain plants, or groups of plants.

Thats cause I didn't know what the hell I was doing (mainly with brachys)

You definitely have a large collection of long term awesome plants. So I don't always understand where you're coming from when you mention problems in your culture, and then discount any proposed solutions.

Thats what I've been trying to say....That the long term plants have always had a good amount of K.

 

[Rick]

So maybe my fert at the moment is on the lower side of standard but still plenty of K. I don't know the Ca an Mg content of my water but I would guess it is low. The mains water is slightly acidic. EC is 0. For the paphs I use 50/50 rain/town water.

So you've lowered K and are concious of the K-Ca/Mg relationship.

So do you want to try going back to something with more K?

 

[Rick]

I don't know the Ca an Mg content of my water but I would guess it is low. The mains water is slightly acidic. EC is 0. For the paphs I use 50/50 rain/town water.

EC of 0? Distilled or RO right out of the tap? Can you get a hardness value from your provider?

 

[Rick]

I find that when I have these problems (and everyone does) It's usually caused by neglect of some kind. The fact that we try to grow orchids from so many different climates and habitats in one area with the same techniques we're always going to have problems. When I see the boom and bust thing Its always caused by deterioration of the p/media. The substrate begins to decompose and it takes the roots with it. You wont see that happening in a plant thats growing faster than the media deteriorates.

I used to think that too. I grow in a smaller GH than you, and was always searching for the perfect micro-climate for the plant that wasn't working out. But changing ferts has made a big chunk of the environmental differential thing irrelevant. The "difficult species, and slow growers" are just as easy now. As long as I keep the humidity high, and temps even, then I just play games with light levels. However, I'm still not ready for true cold growers like Draculas and Masdevalias.

I've also witnessed the boom and bust condition for mounted plants so no media breakdown to explain those busts.

 

[keithrs]

However, these wouldn't be deficiencies caused by lack of resource as opposed to antagonistic deficiences caused by excess of a resource.

Not sure what you mean by antagonistic deficiencies!?!

 

[keithrs]

If you remember one of the threads started by Chris in Florida, with his terrarium system. He doesn't fertilize/supplement at all and posted rainfall data (going back to natural levels of nutrient availability) indicating that deficiences from lack of fertilizing are really a fantasy.

What are deficiencies from then?

I thought Chris just bought some MSU? I could be wrong.....

Perenial plants growing in the wild do just fine at nutrient levels a fraction of what we pour on our plants. I never fertilize the plants/trees/ shrubs on my property nor the woods across the street (which I don't water either). And they seem to do just fine without truckloads of fertilizer being dumped on them.

Trees and shrubs are far different than orchids.... They have relations with fungi, nematode and other things that break down the leaf litter to use as food and massive reserves. Take away those relation and see how long they live for. Orchids(slippers) have adapted to using broken down leaf litter for feed but there most be a constant supply for the plant to have any chance at surviving.