Citrate test

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Rick

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Why are the plants yellow to begin with? :poke:
I suppose you want to say: why your leaves are turning yellow?
read :Here specialy the before last cause.
It may be also in relationship with the all nitrate fertilyser. A pinch of ammonium is not nocive. I am now using a fertiliser having 1/6 of its nitrogen in ammonium form because we have observed the same leaves yellowing with our Belgian MSU version.
 
I suppose you want to say: why your leaves are turning yellow?
read :Here specialy the before last cause.
It may be also in relationship with the all nitrate fertilyser. A pinch of ammonium is not nocive. I am now using a fertiliser having 1/6 of its nitrogen in ammonium form because we have observed the same leaves yellowing with our Belgian MSU version.

Not exactly.... I was not asking why the leaves are "turning" yellow.
For the most part Ricks plants are not yellow so my question was directed at why these particular ones are yellow. I'm interested to know what is different with these, without assuming his fertilizer formula is not correct.
 
For the most part Ricks plants are not yellow so my question was directed at why these particular ones are yellow. I'm interested to know what is different with these, without assuming his fertilizer formula is not correct.

Yes my question to figure out why particular plants and not universal.

My first whack is that nitrate uptake causes an alkalinity buildup in the roots.

So you need an acid sink to void the OH or you will reduce the uptake of nitrate. Also several metal become non available if root environment pH goes up (especially iron).

Now if you water a lot with low alkalinity you can counter OH buildup. Add more moss, use ammonia instead of nitrate (see Brabantia's comment).... lots of ways to skin the "cat".

But since plants make and store lots of citrate and malic acids to specifically counter the above alkalinity dilemma, I thought I'd give this route a shot.



But
 
Yes my question to figure out why particular plants and not universal.

My first whack is that nitrate uptake causes an alkalinity buildup in the roots.

So you need an acid sink to void the OH or you will reduce the uptake of nitrate. Also several metal become non available if root environment pH goes up (especially iron).

Now if you water a lot with low alkalinity you can counter OH buildup. Add more moss, use ammonia instead of nitrate (see Brabantia's comment).... lots of ways to skin the "cat".

But since plants make and store lots of citrate and malic acids to specifically counter the above alkalinity dilemma, I thought I'd give this route a shot.
But

You said you "think" you say greening of the leaves the next day. That is something have have seen recently also. I've been testing a seaweed extract product being made by a Peruvian company. Used as a foliar spray I noticed leaves were darker green the next day. Can't explain the rapid reaction.
I started combining Humic/Fulvic acid with the seaweed spray and the result is darker green leaves in a rapid response.

I'm applying the mix only to the foliage and aerial roots on Phals and not watering the media. Are you using the citric acid in the irrigation water along with fertilizer or as a foliar spray?
 
I'm applying the mix only to the foliage and aerial roots on Phals and not watering the media. Are you using the citric acid in the irrigation water along with fertilizer or as a foliar spray?

Total irrigation drench, but spraying the leaves too. Came across a paper on effects to sweet basil, and it needs to go through the roots for max effect (comparison of foliar trial to hydroponic trial).

And to be specific, I'm using lemon juice which has about 1g/oz of citric acid and about 1/20th malic acid + and whatever unknowns.

Since just about every plant makes citric and malic acid, it should be in kelp products too. But since I stopped using kelp a long time ago its not part of this trial.
 
Total irrigation drench, but spraying the leaves too. Came across a paper on effects to sweet basil, and it needs to go through the roots for max effect (comparison of foliar trial to hydroponic trial).

And to be specific, I'm using lemon juice which has about 1g/oz of citric acid and about 1/20th malic acid + and whatever unknowns.

Since just about every plant makes citric and malic acid, it should be in kelp products too. But since I stopped using kelp a long time ago its not part of this trial.

Since I see a similar rapid green effect without the soil drench maybe your results are not do to altering the root zone as much as altering the leaf.
I don't remember if the seaweed extract I'm testing has citric acid but it is very different from the typical kelp, I think I sent you a copy of the analysis some time back. I'll try to find out if it does have citric acid.
Have you tried using humic/fulvic acid instead of the citric?
 
Have you tried using humic/fulvic acid instead of the citric?

Nope, but lots of precedent for citric acid already.

1)Frequently used as a metals chelator in fertilizers now
2)Frequently used as a pH regulator for commercial greenhouse irrigation water.
3) Plants naturally contain citrate and malic acid in them to use for things like Nitrate transport.
4) Citrate is a common ingredient in orchid flasking media

5) I used lemon juice a lot lately for removing hard water deposits from plant leaves (Stone hates that white @%$@$ on my plants), and I noticed a bump in "greenness" a day or so after cleaning off the leaves. Lemon juice contains about 1 gram/oz of citric acid and about 0.05g/oz of malic acid.

Although this would suggest a foliar input, that 1977 link I attached (under the pics) would suggest this is primarily a root zone function. But this is really hard to separate in practical application. For instance after wiping off the leaves I would hose down the plant so whatever was on the leaves would drip down to the roots.

Might also look to see expected citrate exudates from mosses and lichens.
But there is also a lot of pH regulation that goes on in the rhyzosphere that goes on between the plant, bacteria, fungi, and bryophytes.
 
Probably the acid reduced the pH.

Well I checked pH for a 1/tblspn per gal addition and the pH is low (~4.0)

But I'm also starting out with very low alkalinity in the irrigation water, so easy to push pH down. I'm going to check different dilutions of lemon juice for pH and alkalinity.


Also noting that lemon juice has quite a bit of calcium, magnesium, and potassium (!!!)

So certainly not a very controled way of testing citrate only.:wink:

Although it seems to be producing all around positive results.
 
The Ag supply stores here have 50kg sacks of Citric acid. I have no idea what they use it for. I'll have to ask. It cant be to lower pH because low acidity here is a major problem.

http://www.ces.ncsu.edu/depts/hort/floriculture/plugs/alkalinity.pdf

Here's a pretty good article on the use of various acids (including citric) for adjusting irrigation water pH / alkalinity. It also has a pretty good treatise on the difference between pH and alkalinity, with the correct application of acids based on alkalinity control rather than pH.

I believe there's a lot more to the story of citrate and malate than just pH.
 
Ok

After taking a series of dilutions to the lab, my starting pH of my fert/irrigation water is 6.8su with alkalinity of only 20. It only took 1/8 - 1/4 tsp/gal of lemon juice to drop the pH to around 5.0 - 5.5.

So 1tblspoon per gal is major overkill if you're not battling a bunch of stored alkalinity.

I need to run a couple pour through's.:wink:
 
Isn't citric acid - lemon juice - very unstable? The buffer system of a given amount of water usually is tending to return to the first values, more so if in contact with any kind of substrate. Ask someone with fish tanks!
Years ago I tried to reduce the pH of my aquaria with lemon juice (and with wine-vinegar without sulfites) and the resulting mess (yes I did know before, but somehow didn't want to believe it) was terrible. Lemon juice was directly - two hours!! - transformed by bacteria into white clouds (=more bacteria!) which consumed the oxygen of the well aired tank; I had to evacuate all fish and shrimps - they survived all - and after changing the complete water body three times, the aquarium was stable again, with the same pH it had before the catastrophe.
Quint essence: organic acids are readily consumed by soil bacteria (essentially the same in water bodies) wich feed the plants.
If you want to reduce the pH consistently, you'd have to use a strong acid (HCl); it works and favours ... algae!
But of course, for plants the use of citric acid with this side effect would be desirable.
 

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