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Soil Ph changing during a run - real mystery here

flylowgethigh

Non-growing Lurker
ICMag Donor
It would be nice to rename this thread soil PH changes with plant activity.

I am floundering my way through my first run. I am using 1/3 coots mix amended with BAS stuff. The plants are in 7 gallon bags and I Ph adjusted the soil to 6.8 before the start with some oyster meal. The plants appear to be doing great finally by the growth and leafs. I am using a SWICK (bags on a SIP bed), and adjusting my tap water down to 6.5 in the reservoir, and have to do so between feedings because the water exchange with the plants raises the PH of the reservoir. Like up to 6.8 or 7.0 if I let it go two cycles (12 hours).

So the soil is raising the water Ph somehow. I have a Ph/moisture meter that started working pretty well, until I inoculated the plants in bags. and then it was acting funny measuring the soil in the bags, like it is short circuiting when I test the soil in them. I wrote it off as just being more chinese junk, but today I tried it again and it seems to be working OK. Readings of my lawn, extra soil, garden... all the same as they were when I got the probe, 6.6 to 6.9.

This is what the bags the plants I'm about to flip in a week or so show...

Click image for larger version  Name:	DSC00312.JPG Views:	0 Size:	86.3 KB ID:	17812346 Yeah, that says 4.5!

The needle goes straight to that reading like it means it. All 4 plants read about the same...


I have to believe something is going on, and I wonder if the soil has good cation exchange capacity now and is freaking out the meter.

Anybody have a clue? Here's one of the plants, growing like a weed.

Click image for larger version  Name:	DSC00313.JPG Views:	0 Size:	105.3 KB ID:	17812347

I feel like I shouldn't worry and do anything drastic. How can soil that is making the water higher in Ph, read lower... way lower, than it was? The only thing I can figure is there is a lot of ion exchange going on finally in the soil in the big tent. This may be a way to know if the soil system is working properly.
 
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flylowgethigh

Non-growing Lurker
ICMag Donor
My res is bubbled 24/7. Starcrash, yup - so why mess with it? I am just curious. I was talking with Chris at Redbud Soil, and the best we can figure is the meter is being zapped by all the cation exchange capacity (CEC) that the living soil has. This is only a cheapo chinese meter, but I sorta believe it. When the soil gets inoculated, charged with Ca+ nd Mg+ ions, Ph dropped with H+ acid, things get electrically active. Maybe that is why I have to keep the soil so moist.

When I first inoculated and up-potted from dixie cups, the meter would swing between 7 and 4 like it was shorting out. The soil I have in waiting for the next run does like this soil used to... move right almost to 8 before slowly lowering to 6.7 or so. It started doing that after I put the oyster meal in to raise the Ph from around 6. So whatever oyster adds electronically, it works the opposite as the stuff that sparks it up.

I'm just guessing, but I have some yellow clay soil (dirt) that is pure garbage, and needs humus and cations bad. I have limed the crap outta it already. I wonder if I inoculated it with a sprayer???
 

40degsouth

Well-known member
Hey everyone,
Flylowgethigh, could it be that the bagged soil isn’t fully composed and components within it are running at different ph’s??? For example pine bark and compost. Maybe it hasn’t been mixed thoroughly, so some parts acidic and some a bit limey??
This might be one reason for the rapid swings??
What about litmus strips laid in the soil??
40.
 

flylowgethigh

Non-growing Lurker
ICMag Donor
Mr 40*S, Thanks for reminding me of the litmus, I was thinking the same thing then burned a doob, and promptly got distracted. I have pool test strips for the pond that I can use. The compost stuff in the soil is who-knows-what. I have some black kow which has a lot of chipped wood, but I don't think that is the issue, because the other soil I have is stable. When I pot the next run with some of that soil, I will do a before and after inoculation test, to see if that is it.
 

f-e

Well-known member
Mentor
Veteran
If the root zone pH drops, a plant will correct it in its efforts to eat. You may be washing out it's hard work. Signs of too low a pH can be light green plants.
 

flylowgethigh

Non-growing Lurker
ICMag Donor
I am high and guessing out loud here, so sorry. But not very sorry.

This Cation exchange thingy is key IMO. The yellow clay I deal with down by the pond is probably CEC negative. The stuff will not grow fescue, as-is. The seed will sprout, grow until it eats itself, and die. Like it cannot feed off the generous chemical farmer nutes I apply .When it is dry and I am turning the dirt, it is social distancing from itself. Does the same in the pond and won't settle - stays suspended. Put aluminum Sulfate in and the particle charges neutralize, the clay drops to the bottom, and the water is clear. It also drops the Ph drastically. Pros buffer that with bicarbonate. I just put up with the yellow/brown water.

https://en.wikipedia.org/wiki/Cation-exchange_capacity

Living soil probably has a real high CEC. Who knew vermeculite did too? Hmmmm.

Living soil is supposed to be OK with a wide range of water Ph. Maybe the CEC is why. I think making my Ph 6.5 water with cal/mag or epsom salts is helping the Ph 6.8 soil..

<
Cation Exchange


Cation exchange can increase alkalinity whenever hydrogen ions in solution exchange on surfaces for base cations. The effect is generally reversible, and thus the process may not contribute to long-term increases in alkalinity once the cation exchange sites are depleted. In fact, cation exchange can act in reverse if base cations are added from sea spray or road salt to a soil solution, causing temporary acidification and loss of alkalinity. Nevertheless, soils with large cation exchange capacities can act as a large buffering reserve against relatively short-term acidification events.>

View chapterPurchase book
https://www.sciencedirect.com/topics...ation-exchange

This article on CEC has an interesting warning...

As plant roots take up cations, other cations in the soil water replace them on the colloid. If there is a concentration of one particular cation in the soil water, those cations will force other cations off the colloid and take their place.

https://www.dpi.nsw.gov.au/agricultu.../structure/cec

Good article, especially in my situation. Colloid - that sounds like my yellow clay. The dirt I dug from my pond is yellow clay like the stuff at the bottom of this pic, and below it is white rocks with prehistoric sea shells in them. Same color as the white stuff below in the pic. This is why I'm interested in Humus and CEC, cause that soil had none. I have limed it (calcium ag lime) very thickly, and had a lot of chicken shit applied. Looking back, that was smart for the K, but I wanted humus and it makes a hellova tea.

I also mixed in some topsoil stripped off the farm next door, that I kinda jacked last summer. The area was seeded and fertilized last fall and fertilized again 2 weeks ago - and it looks great. CEC is real. I have only applied Ca and K, and need the Mg too. The K is thick in chicken chit, and I also use a lot of farmer 17-17-17.

Where to get Mg? Dolomite lime around here is from the bottom of an old mine chem separation pool, per the farmer who spreads my lime and CS. Nope.

What is the colloid in the living soil? My yellow clay when dry acts like the big negative plate, with no positive ions. Like this pic. Damn that looks like the deck of an aircraft carrier with a bunch of planes loaded with ions ready to launch. When this is working I can see it short circuiting the Ph probe somehow.

cec-diagram.gif


I have heard of soil recipes that added some clay. Is that to put the colloid in?

Yellow clay: Notice how the topsoil in the pic below is red clay, but has lotsa humus. That yellow stuff on the right side - the same layer as below, is what I am dealing with. Just looking at it, one might think it was OK. A little deeper and the white rocks start. This pic is a couple states away, yet the same kind of layers sorta..

800px-Providence_Canyon_from_rim.jpg


So my loaded thinking has me wondering about the compost I used in my soil. Who knows what was used to make it. We need Magnesium in the plant because it is the centerpiece of the chlorophyll molecule. Adding cal-mg is making my plants grow leafs a lot better. Grass has a bunch of chlorophyl, and I am spending a bundle making mine grass make a bunch of chlorophyll. I need a grass clipping catcher on my mower, and also use it to collect the leaves from the oak trees. There's hardwood branches I have to pick up each year too (like right now)... I am going to start using MY materials to make MY own mulch/compost. And raise my own worms, and have the castings and juice too. At least then I would have a stable baseline to amend from. Maybe lose the cal-mag and epsom salts.

All this started at the beginning of Jan, when I decided to start growing inside, instead of buying and transporting dope, because my vaping habit wanted better terps. It was an experience running around the local garden places trying to find stuff. In January, when NOBODY around here is thinking about gardening, and the shops are down to what's left over from last year. I had no clue what any of the stuff was, or what I needed. Way illegal state, so I had to say I was gonna start growing "heritage tomatoes", like all redneck preppers are supposed to be doing. I could tell one store was catering to growers a little, but just nutes mostly and HF products. Can't talk about growing. I guess places like that are good for peat, and fish / worm feed.

The big take-away so far from my growing experiment is sourcing the inputs, and soil is key and requires local inputs. Soil very well may be my next hobby. I have the inputs for it.
Providence_Canyon_State_Park
 
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40degsouth

Well-known member
Hey Flylowgethigh,
Steve Soloman has stated that humus cannot form without clay. Personally l think it’s an important addition to any soil right up there with biochar.
(Rico Swazi, over at the “Local Materials” thread has posted some information to the contrary, believing it to be carcinogenic and posting supporting links)
Are you trying to grow in the clay itself and get a garden bed going???
40
 

chilliwilli

Waterboy
In my corner of the world i can get rock dust called zeobas its a mix of zeolite with basalt that should raise the cec. Zeolite/bentonite should help if u want to raise the cec in a mix.
Tried on my first notill mix(notill team microbe(coco no sphagnum)) with a cup/cu ft in addition to the mix and got about 5 runs with water only before i started to add some ferts again.
New mix is with sphagnum and no zeobas and after 3 runs i got slow veg grow, overall light plants and less stretch in flower.
 

40degsouth

Well-known member
Zeolite’s a fantastic soil additive, it has the ability to hold onto cations and anions and give them up freely. This means that fertiliser costs, or applications are greatly reduced. It’s also good for water retention. Unfortunately where l am it’s really expensive and my soils are vast.
l did research bentonite fairly extensively, at one stage and from memory, the cheapest form was non clumping, cat litter. Obviously there can be some pretty nasty ingredients, so I’d recommend checking the ingredients first or contact the manufacturer and just make sure.
The reason l ended up going this way was because the powdered form, garden specific, was sooo expensive.
40
 

flylowgethigh

Non-growing Lurker
ICMag Donor
From the dPI link above, the CEC levels vary...

Humus


CEC varies according to the type of soil. Humus, the end product of decomposed organic matter, has the highest CEC value because organic matter colloids have large quantities of negative charges. Humus has a CEC two to five times greater than montmorillonite clay and up to 30 times greater than kaolinite clay, so is very important in improving soil fertility.
Clay


Clay has a great capacity to attract and hold cations because of its chemical structure. However, CEC varies according to the type of clay. It is highest in montmorillonite clay, found in chocolate soils and black puggy alluvials. It is lowest in heavily weathered kaolinite clay, found in krasnozem soils, and slightly higher in the less weathered illite clay. Low CEC values can be improved by adding organic matter.


https://www.ussilica.com/materials/montmorillonite-clay << cat litter.

I am going to look into if BAS has clay as part of their soil kit I used. I might need to add a little cat litter, which may also aid drainage (wicking).
 

flylowgethigh

Non-growing Lurker
ICMag Donor
From that same DPI article, they explain why my pond water stays brown and cloudy... "When exchangeable sodium is present in quantities greater than about 5% of the CEC, it makes the clay particles unstable in rainwater. This shows up as dispersion or cloudiness in water. Dispersive soils have poor water entry and drainage and set hard on drying."

I can take a 5 gallon bucket of that dirty pond water, take a pint jar of water and add a tsp of aluminum sulfate and shake it to mix, pour and stir it into the bucket, and the water will clear up in minutes, leaving the clay on the bottom, no longer socail distancing. That is called "floxulation", and it's how they clean swimming pool water.

So I re-inoculated the soil in the veg tent (misfits and midgets). It read a solid 6.8 Ph before, and the needle swung high before settling at that number. This morning the soils test lower PH, and the needle swings left to the number, never going higher before settling down. One plant was 5.6, the other two around 6. Strange stuff, but I think the soil in those pots is sparking now. Why would bacteria and enzymes do that? The soil has to be wet to spark, like electrolyte.

DSC00314.JPG
<<That one's really sparkin!
image_2031922.jpg
<< Not so much but the Ph was 6.8
image_2031923.jpg
Sparks are flyin!! This was 6,8 before the inoculation

Can someone offer an explanation for this?

OK, so while I am on a Mg hunt, what is the stuff we re leaching out when we make kelp/alfalfa tea? Is it chlorophyl, which contains Mg? Cn I dd grass clippings to the tea mix and do any good?
 

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Creeperpark

Well-known member
Mentor
Veteran
To be honest, I have never had any luck with probe meters that you stick in the soil . They are very unreliable and give false readings. 😎
 
G

Guest

G'day Cobber. I think you're overthinking things. Just keep doing what you're doing. The plants look fine. WHEN and IF the plants begin to look crook ... that's the time to start thinking. Of course , if you've nothing else to do ...
 
G

Guest

for ph measure your runoff to get an accurate reading..

Measuring run off of soil is useless. OK in hydro ... but not soil. You will always get a 'too acid' reading. (Unless of course you've got super alkaline soil but then yr plants wouldn't be growing anyway.)
 

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