Fertilizer and some problems...

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SelectOrchids

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I have just read the post on the RO fertilizer.

To me:

- The powder fertilizers are NOT stable
- The liquid fertilizers are NOT stable, and I would strongly suggest against doing a liquid concentrate of any given fertilizer.

Let just have a simple look at some basic chemistry and how to understand the problem:

* A fertilizer is composed of several salts, blended or dissolved together. You must read the composition of the fertilizer, both the percentages and the 'derived/made from ammonium nitrate, potassium dihydrogenphosphate, etc...', that is included in the fertilizer, or downloadable on the internet from most if not all the serious fertilizer manufacturers.

* Calculate the weight of each of those basic salts. It can be done with Excel as an example. If the fertilizer says as an example

"Fe from Fe chelated EDTA", we know that the Fe EDTA contains 0.152% of Fe, 100mg of Fe chelated by EDTA contains therefore 15.2mg of iron.

It is just boring to make the calculations, but for those ones who want to do in detail...

* Download
http://www.lwr.kth.se/English/OurSoftware/vminteq/

Visual Minteq is a freeware which can be use for a wide range of purposes. For our purposes, we enter all the mineral salts from the fertilizers, and can modelize the chemical reactions that will happen when all those salts are put together, 'nearly dry' or in stock concentrate solutions. Visual Minteq is highly reliable...

We found easily that for all except the most basic NPK only fertilizers, some precipitate will occur, eventually locking completely one nutrient, micro or macronutrient. Especially around the calcium/magnesium/phosphate/sulfate story for the macroelements, and the Iron/Copper/Calcium/EDTA/EDDHA for the microelements.

Having a 'dry' fertilizer is impossible, as first we have hydratation molecules of some of the salts. The calcium nitrate is in the tetrahydrate form for the fertilizer production. The anhydrous stage can be sometimes found, but it will hydrate easily, so it is not that useful...

Second, the air humidity will anyway bring water molecules in the powder. There is nothing to do against that.

With MinteQ, you can modelize how the powder will perform, by increasing the water content to a very small quantity. This explains why for many fertilizers, a precipitate will occur when they are dissolved. Anyway...

For the stock solutions, like 50g/L or that kind of stuff, the problem is far more dangerous. The precipitate occurs at the molecular, or microaggregate levels, so it cannot be seen by the naked eye. We make what is called a colloidal solution this way, when the precipitation will occur, the resulting useless for the plant molecules will disperse more or less evenly in the solution. This reaction can take some seconds or some hours. Anyway, the proper way to make a quick to use stock solution is to put the powder in the water, not the water on top of the powder, as some compounds can form extremely quickly, like calcium sulfate or calcium phosphate...

One way to delay the problem is to make the solution very acidic, but it is not practical, as after we have to correct the pH of the water/fertilizer solution. And the EDTA/EDDHA chelated compounds can make funny things at very low pH required to keep the calcium, phosphate, sulfate, and magnesium safely as ions in the solution... There is no 'best solution' actually...

This is again for people who really want to fine tune everything, because at the practical level, most fertilizer will do well by themselves, even with the lost micronutrients or a part of the macros that are precipitated.
 
So is there a solution? I know you say there is no best solution so what would you suggest as a result of your findings above? I use very little fertiliser anyway and I haven't found the stability to be a real problem with growing my plants.
 
I think, most users are with that mix of fertilizer overtaxed.

The important asks is: what fertilizer need our plants?

In my greenhouse Paphs. are in growth, rooting, blooming....Cattl. are resting, flowering .... L. purpurata is the growth not ready....

Higher N or P....?

I thinks the best way is a fertilizer in a component system:

standard NPK + micro nutrient + amino acid and vitamins + organic fertilizer ...
 
My concern is that I am a new grower with many paphs.(Of course, after my large spending spree the last few months,I have to slow down). Slippers have grown well for me since I started with orchids almost 2 years ago.This spring,I had a few rebloom! This fall and winter I've been rewarded for my culture with lots more blooming.
My first watering is with lukewarm tapwater using a gentle sprayer. Second watering, about 10 min later, I had been using tap water that sat for a few days to remove chlorine, mixed with distilled water.When I fertilized, I used Dynagrow liquid fertilizers in low doses,epsom salts. I grow in bark mix, occasionally adding a little leaf mold, chopped fern roots, ect.. from our woods! My slippers love it!
Now, I have an RO system and above all, want to do no harm to my beauties! 1st watering I used the Dynagrow and Protekt with the RO water.Received my powdered RO fertilizer last week and hit the internet to look at all info on it.Newbies tend to worry about new stuff! I am not looking for a product that will cure any cultural mistakes, I want to be confident that the product I am using will not impair the health of my slippers.
What do you suggest? With the dynagrow,I mixed the fertilizer less than full strength into a gallon of water, 4 gallons at a time. I didn't leave any mixed solution for another day. Would it be better to continue this practice with the powder?
I am not really fond of the idea that the vendor repackages the product as I do not know if other vendors would be as conscientious as Ray. In fact, one of the first things I thought after reading that post on orchid forum was pitching this fertilizer from KK and reordering from Ray!
Believe me, any and all input would be appreciated!
 
I thinks the best way is a fertilizer in a component system:

standard NPK + micro nutrient + amino acid and vitamins + organic fertilizer ...

This actually sounds like a good idea to me: keep the individual components separated as much as is necessary to ensure stability and bioavailabilty and only mix them together in solution at the last possible moment before making application to the plants. The measuring and mixing instructions would need to be very clear and precise in order to keep the proper nutrient ratios and bioavailability intact. It's not the most practical approach. Not everyone would be interested in doing it, but I think many of us would be willing to devote the time and effort if we felt it was the best way to keep our prized plants properly nourished. I would purchase a fertilizer "kit" product such as this, one which contains all the individual components with mixing instructions, if it were to be made available for purchase.

I wonder if using only "natural" type fertilizers would be a viable alternative method of supplying all the nutrients and micronutrients our plants need; or perhaps certain "natural" products would be better sources of those specific nutrients or micronutrients which in a chemical solution are most likely to precipitate into forms which are unuseable by our plants. The "natural" type fertilizers I am referring to are things such as the liquid extracts of kelp, fish, cottonseed meal, earthworm castings, bat guano, molasses etcetera.
 
- The powder fertilizers are NOT stable
- The liquid fertilizers are NOT stable, and I would strongly suggest against doing a liquid concentrate of any given fertilizer.

Doesn't that disregard the time scale?

The powdered fertilizers we buy are predominately inorganic chemicals that are infinitely stable if stored properly. Once in solution, you may find some precipitation if chilled or kept for a long time, but that can be very easily dispersed and redissolved.

The minuscule organic contributions tend to be in forms intended specifically to be stable, but that can be deteriorated by moving it into acidic pH ranges - which is what happens in solution. Iron-EDTA is good for well over a year by itself, but even if cut in half by dropping the pH, that's still pretty stable.

I think the most significant thing coming from this discussion is that one should gauge the size of the container purchased and concentrate made to be consumed in a matter of months.
 
I believe there are at least two forms of iron and other chelated nutrients of that type, depending on what type of pH environment it's going into, to try and allow the product to be most useful in the solution you want to make. yes you should be careful with cal mag and sulfur (maybe more compounds than just sulfur). supposedly 'professional' bag mixes won't put sulfur in the same bag with cal/mag, and if you mix different types you will get sludge and frost on top and outside of the barrel. it is a big problem that in general (not talking about fertilizers where someone has thoughtfully made up a formula for orchids in general) historically, fertilizers have been made by companies that want to provide something that they think a lot of companies will buy, not because they did testing and found that all of these different things did or didn't work well together, or that they had a vision and know that this particular mix will work great. some mixes are really meant for just geraniums, others this plant or that one. sometimes big companies ask for a certain formula and if they buy enough fertilizer the company will often make it (it doesn't mean that it will particularly work, just that $$ talk...)

often fertilizer companies that sell large bags that will likely end up in a stock solution barrel will suggest that a mixing apparatus like a propeller-type thingy or an air bubbler will constantly mix the solution.

components of fertilizer that have different particles are mixed (more from a question from other thread) on an assembly line type machine; six eight ten different hoppers will drop each thing at hopefully controlled rate onto the belt, then put into a larger hopper, then dumped into bags. it's true that if you are mixing a gallon and taking mix from 25 lb bag, you will often see more of this here, less of that there, making you wonder just how even it is. for a vendor that is repackaging, I wouldn't worry about it too much. they are taking from a big bag and just putting it into a smaller one. I think if you use just a little, then maybe you should put your small pound or so that you got in the mail and put it into something larger (airtight) maybe and shake it all around so hopefully evening it all out. it's the same as our soil mixing machine. those big bags are really meant to be dumped into a big barrel of water either for stock solution or a big tub so at finished rate, not to have a few teaspoons taken from them every once in a while. I think some bags even say on them 'for professional use only', for people that understand why certain things are better to do than others... though, it's a free world, but like ray says, buy the container of dry or wet that you can mix up and use in as short a time as possible.

one thing I forgot to add before, if you really want to water plants with compounds that are maybe not compatible (calcium and sulfate etc), mix one part to final hose ppm solution, then either apply then later do the other the same; or mix them both to final application rate in separate containers and then pipe them together and apply as one. things that will cause problems in stock solution generally won't at the final hose rate
 
Good point and to the heart of the matter! The 3 lb size was way too big for my needs. Will split the dry mix and keep in several well sealed containers. Thanks everyone for their input on both posts!! It's great to have knowledgeable folks to go to for help or with our concerns!! Thanks again!:)

I think the most significant thing coming from this discussion is that one should gauge the size of the container purchased and concentrate made to be consumed in a matter of months.
 
I have just read the post on the RO fertilizer.

To me:

- The powder fertilizers are NOT stable
- The liquid fertilizers are NOT stable, and I would strongly suggest against doing a liquid concentrate of any given fertilizer.

In reading your post, I have the impression that here is no solution to the problem. Powder fertilizers are no good; liquid fertilizers are no good; you can't keep it dry (humidity); you can't make it acidic to delay the reaction.

But thousands and thousands of growers grow big healthy orchids using just about every liquid/dry fertilizer available. So, is it really a problem we should be concerned about?

Gary
 
In reading your post, I have the impression that here is no solution to the problem. Powder fertilizers are no good; liquid fertilizers are no good; you can't keep it dry (humidity); you can't make it acidic to delay the reaction.

But thousands and thousands of growers grow big healthy orchids using just about every liquid/dry fertilizer available. So, is it really a problem we should be concerned about?

Gary

Well said, GaryB. :) Hammer hits nail on head. You win the prize. It's a hobby, do the best you can.

-Ernie
 
y'know, I was reading a book about 'jungles of the world', and the author was explaining that during the many monsoonal storms, when there is a lot of lightning there is actually nitrogen pulled from the air and turned into some sort of compound that fell by the ton (over a year over a very wide area) on the rainforests as 'fertilizer'. I had never heard that claimed before, but if it's true then could explain how these plants that get oodles of rain actually get some nutrients in, instead of washed out

anyone heard of this before?
 
I have heard that lightening pulls nitrogen from the air, so it makes sense that it falls in the rain and fertilizes plants.
 
y'know, I was reading a book about 'jungles of the world', and the author was explaining that during the many monsoonal storms, when there is a lot of lightning there is actually nitrogen pulled from the air and turned into some sort of compound that fell by the ton (over a year over a very wide area) on the rainforests as 'fertilizer'. I had never heard that claimed before, but if it's true then could explain how these plants that get oodles of rain actually get some nutrients in, instead of washed out

anyone heard of this before?

I have heard that lightening pulls nitrogen from the air, so it makes sense that it falls in the rain and fertilizes plants.

Yes, I've heard of this too. I had forgotten about it :eek: but I had in fact heard of this many years ago. I believe it is true.

So if you want to avoid troubles fertilizing your plants, just stick a live electrical wire in amongst them and then spritz away with your water bottle! :p :poke: :rollhappy:

No, don't! :drool: I was notti to suggest it. :evil:
 
Yes...lightning is a nitrogen "fixer"...I believe it combines the nitrogen with oxygen to form nitrate, but I may be wrong. Also its possible that any cyanobacteria (blue-green "algae") growing in a humid area around the roots could fix nitrogen.
 

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