Slownickel lounge, pull up a chair. CEC interpretation

[led05]

So at such a low pH the CEC sites start being taken over by hydrogen and aluminum. The reason why the aluminum is such a problem at low pH is that it goes from aluminum oxide to trivalent aluminum, which takes over CEC sites and leaches out other bases. TCEC is not equivalent to CEC, it's is much much lower. This is because sites occupied by hydrogen and aluminum will not removed by any other single ion, you need a change in the chemical environment. What would want to do there is raise the pH with lime. This will give an actually CEC number.

PH target closer to 7 than 6, been saying this long time - It's the grand compromise to what's discussed the past 3-4 pages and past 200-300 pages...... If you grow a number of varying crop species you may already know this...

Most soils head toward acidic over the season, consider this - many factors cause this but generally speaking things are becoming more acidic than basic in farming soils

 

[growingcrazy]

Without leaching, is CEC of concern in a peat based medium?

 

[led05]

How and what do you use for foliar application?

Various spray method delivery, Cal Carb in a very pure form, base water is RO - PPM < 2 - and nothing else, I believe that is critical aspect

 

[plantingplants]

Hey everyone, I topdressed this soil with 50 lbs gyp in early Jan. Do you think it's good to go after I wash the gyp through a little more? The CEC is around 35, which puts K around 5%. I'm sure leaching the gyp will lower everything (from heavy irrigation and gyp knocking off cations) but IME it doesn't change a huge amount. So all I can think is maybe needs a little chicken manure to get poppin'.

Otherwise, should I do anything to the pots to freshen them up? Is it worth it to till the whole 24" just to till it? Aeration? Worth the labor to till some stutzman chicken manure in or just top dress?

 

[paradoxlost]

Guys, isn't the calculation in part a plug? i.e. it's a calculated value not a measurable one for some aspects?

Everything has limitations, even soil tests

CEC is definitely a directly measurable parameter, or I guess I should say fairly directly. Sum of bases is a less than ideal way of determining that, cause when your metals get high they start to occupy sites.

But yea every test has assumptions that go along with it that limit where you can use those numbers for sure.

 

[paradoxlost]

PH target closer to 7 than 6, been saying this long time - It's the grand compromise to what's discussed the past 3-4 pages and past 200-300 pages...... If you grow a number of varying crop species you may already know this...

Most soils head toward acidic over the season, consider this - many factors cause this but generally speaking things are becoming more acidic than basic in farming soils

This is definitely true. How fast it happens I don't know. Most nutrients are most available around 6.5, but than the bad ones start coming in lower than 5.

Also I should add to that previous post of mine at low pH trivalent aluminum also hydrolyzes water, increase hydrogen ion concentration

 

[Alg0rithm]

Various spray method delivery, Cal Carb in a very pure form, base water is RO - PPM < 2 - and nothing else, I believe that is critical aspect

What do you mean by 'Cal Carb in a very pure form?'

Biomin amino chelated Calcium first came to mind..

Any particular brand/product you could recommend?

 

[led05]

What do you mean by 'Cal Carb in a very pure form?'

Biomin amino chelated Calcium first came to mind..

Any particular brand/product you could recommend?

I use an extremely fine powder form of very pure (I believe it was > 99.9% CaCo3) I bought a shit-ton of a while ago, Ca is 30-35% range. I use 2-3tsp / Gallon, this never clogs any of my spray methods and provides more than an adequate amount of Ca.

IME, the cleaner the Ca product and starting water (RO) the better to ensure proper foliar, this goes for any nutrient(s) you're trying to deliver foliarly...

It's extremely clear within 24 hours when you're getting Ca into your plants correctly. Even if you think things already were near perfect.

 

[Hermen_eutics]

Hey everyone, I topdressed this soil with 50 lbs gyp in early Jan. Do you think it's good to go after I wash the gyp through a little more? The CEC is around 35, which puts K around 5%. I'm sure leaching the gyp will lower everything (from heavy irrigation and gyp knocking off cations) but IME it doesn't change a huge amount. So all I can think is maybe needs a little chicken manure to get poppin'.

Otherwise, should I do anything to the pots to freshen them up? Is it worth it to till the whole 24" just to till it? Aeration? Worth the labor to till some stutzman chicken manure in or just top dress?


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Hey PP, were you expecting that S would measure so high (11,600)? Was this a big increase in ppm's of S or did you start high? Also my Zn is also on the high side. I've been trying to detect the source of my Zn (107ppm) wondering if it's runoff filtering into my soil bins from a freshly stained deck??? Have your tests shown hign Zn in other tests?

@Alg0rithm I've been hitting my ladies here and there with the biomin Ca powder w amino's. I have applied foliar and drench.

@led05 what do you observe after applying the CaCo3 that makes you say it's clear that it is effectively getting into the plant?

 

[plantingplants]

Hermen that’s from the gyp. I feed Zn. I think I was shooting for higher actually. Get your water tested maybe?

 

[Hermen_eutics]

 

[Hermen_eutics]

Hermen that’s from the gyp. I feed Zn. I think I was shooting for higher actually. Get your water tested maybe?

I ran rain water through my mix which measured 5kppm. After about 8 weeks it dropped to 3800. You concerned at all about excessive S levels?

What were you shooting for with Zn. I got worried when my ppm came back over 100. My water supply does use a zinc additive to protect against lead, it's minuscule <1ppm. I use mostly r/o or rain water anyway.

 

[jidoka]

1) 9 days after potting up from 1 gal to 3.
2) 0.75 - 2 - 1
3 & 4) some more commercial stuff

 

[EasyGoing]

Is the thread broken for others? I can't load the last page?

 

[MrBungle]

It's actually fixed...

 

[GreenHands13]

Plantingplants. It might mean nothing and it isn't very much different. But it is kinda strange that on your test you have more available calcium with AA 8.2. At that high of a pH you should definitley have less available Ca. That's kinda the reason for doing a elevated pH test for calcium. Maybe a problem with the test.

 

[paradoxlost]

Plantingplants. It might mean nothing and it isn't very much different. But it is kinda strange that on your test you have more available calcium with AA 8.2. At that high of a pH you should definitley have less available Ca. That's kinda the reason for doing a elevated pH test for calcium. Maybe a problem with the test.

The AA test should only be used if you have calcium carbonate, alkaline soils. If you don't than you will leach out more calcium at higher pH.... Something that has been over looked in this thread. Perhaps because of all the native soils being alkaline or to much carbonate soil amending.

This may not be the whole picture though. I feel like there's something there that is influenced by phosphorus and iron as well... But I may be wrong.

 

[bsgospel]

In that case would you use the M3 result instead of the AA? Or would a carbonate/alkaline soil simply be deceptive every time?

 

[paradoxlost]

In that case would you use the M3 result instead of the AA? Or would a carbonate/alkaline soil simply be deceptive every time?

Use the m3 results at pH 7

 

[Hemphrey Bogart]

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