Do we need to pH adjust our nutrient solutions?

[CraZysWeeD]

That's what I don't buy from him. I'm sure it applies with their soil mixes but you cant generalize every pot mix and different kinds of waters/mix like that.

 

[Amy Gardner]

It's the contents of the water that will cause it to drift over time.

Plus the action of the plant - it’s a combined thing. And the action of the plant is affected by what’s in the water too.

 

[Preston9mm]

Make sense to me....
His last answer should be "Yes, depending on the dkh of the water you have been using over time".

Adjusting the ph of the water will slightly adjust dkh. Moreso if your raising it.

Effects of dkh of water are covered pretty well in the saltwater aquarium hobby.

I try to think of it (dkh or carbonate hardness) as the 'ability of the solution to stay at that ph'. It's like ph is a derivative of carbonate hardness.

I don't test for dkh of my nute solution. I know the dkh of my cistern water, maybe I should test it after applying nutes to see it's change, but considering most of the nutes I use lower ph, the effect on the solutions dkh is negligible. I would imagine it to be pretty low, considering how easy it is to adjust the nute solution.

When one goes to carefully 'adjust' the ph of solutions containing higher carbonate hardness it is a little more tricky than just adding some drops to the water.

For most of us, this will be a static factor that we really don't think about as it's not really varying in our daily nute prep. Should growers target dkh? Hell no. Should growers know if they have a hardness issue with their water? YES. Hardness is alkalinity.

Your showing your age when the question was not answered. I only say that because I am there too.

The issues in soil with dkh would be a buildup where nutes could not stay in solution in the soil. Farmers know this (we have crop rotation for this issue and others). So, the evil type 2 error occurs when someone is unknowingly giving hard water nutes over time and they get lockout even though their ph'ed water is right all the time. It happens, your on a well, and/or you have excessive co2 in water.

Hard water where grower A lives is not going to be the same as hard water where grower B lives.

Cool conversation.

 

[InTheShed]

That's what I don't buy from him. I'm sure it applies with their soil mixes but you cant generalize every pot mix and different kinds of waters/mix like that.

You don't have to buy it. He's stating scientific facts for soil and soil-less media. Not for ProMix specifically.

Plus the action of the plant - it’s a combined thing. And the action of the plant is affected by what’s in the water too.

The content of the water determines how the roots respond. This is what he's saying in 2 a-d.

I was experiencing no judgment about either in my thoughts so I’m sorry if it came off like that!

I didn't really think you meant it as a diss.

 

[Amy Gardner]

The content of the water determines how the roots respond. This is what he's saying in 2 a-d.

Yes - that’s exactly what I’m taking about. It’s the part that interests me. Because then what the plant releases contributes to the mix that effects the ph balance and drift (or lack of drift) of the soil.

Edit: pretty much what he says is exactly why/how high Brix growing works and what Doc’s work has been dedicated to tuning his system to. What interested me was the notion that synthetic nutes would also need to be balanced with regard to what they trigger the plants to release and I wondered if perhaps the lines that do this better might be less susceptible to ph problems. Has anyone ever talked about finding some nute lines more problematic than others in regards to ph? I’d be curious, I’m just curious about it...

I didn't really think you meant it as a diss.

Ok! But what do you mean by “you say that like it’s a bad thing” and also what what you said about not turning it into a battle of the grow method? Maybe I’ll just go back to bed... I thought this was an interesting discussion. I wasn’t battle mongering

 

[CraZysWeeD]

ProMix

But they pay his study?

 

[InTheShed]

I wasn’t battle mongering

I didn't think you specifically were battle mongering. I didn't mean to be ascribing that to you. I was hoping my exclamation mark indicated that but it may have been too subtle.

But they pay his study?

This is soil science Crazy, not some paid shill. He sent me links to university studies and farm research that has nothing to do with ProMix. He wasn't even talking specifically about ProMix. You don't need to believe it and I'm not trying to convince you. I am letting you know that his knowledge on this subject runs much deeper and wider than yours, mine, or anyone else I know of here.

 

[CraZysWeeD]

This is soil science Crazy, not some paid shill. He sent me links to university studies and farm research that has nothing to do with ProMix. He wasn't even talking specifically about ProMix. You don't need to believe it and I'm not trying to convince you. I am letting you know that his knowledge on this subject runs much deeper and wider than yours, mine, or anyone else I know of here.

I get it Shed. I'm having hard adapting stuff that goes in stick with my own but I'm always open to listen. In those words I read it sounds like it can handle everything you pour in it an make use of it. It's good to know about it but I feel it's more to it than just the soil. I want to see the proof here, grown cannabis plants. Grown in same soil and watered with different pH one 5, 6 and 7. I'm almost certain you will get three different results.

 

[InTheShed]

I'd make it easier and just run two clones. One pH adjusted and one at wherever it lands after mixing. Wish I had the room for science.

 

[FelipeBlu]

When we talk about soil mixes being pH-buffered, it’s primarily because dolomite lime has been incorporated to counter the extremely low pH of peat moss. This typically brings the mix into balance somewhere between 6.0 and 7.0 pH.

But this balanced pH can be upset. Continued application of low-pH nutrients will reduce the effectiveness of the lime over time. And high alkalinity (hard) water will raise the pH of the media. Take a look at the attached map, courtesy of the USGS:

If you live where it’s white or red, and use tap or well water, the pH of your soil mix will increase over time. If you grow in a high CEC medium (containing peat moss), you may need to flush with RO water once in a while. The upside? You may not need to add CalMag.

 

[InTheShed]

Continued application of low-pH nutrients will reduce the effectiveness of the lime over time.

This is not what his science says. It says that the type of nitrogen in your fertilizer will determine whether your pH rises or falls, along with the raising tendency of high alkaline water.

 

[Marzbadrock]

Hmmmm, I'm right on a intersection of 3 colors!

 

[FelipeBlu]

This is not what his science says. It says that the type of nitrogen in your fertilizer will determine whether your pH rises or falls, along with the raising tendency of high alkaline water.

Absolutely the type of nitrogen is involved! What I wrote was shorthand for “solutions which induce a low-pH-condition”.

 

[FelipeBlu]

If the nitrogen you are using releases an extra H+ ion, it will require more CaCO3 to balance it, or the pH will decrease. At some point, all of the lime initially added to the soil mix will be engaged, and the pH will start to go down.

 

[InTheShed]

Absolutely the type of nitrogen is involved! What I wrote was shorthand for “solutions which induce a low-pH-condition”.

I was just talking about this:

Continued application of low-pH nutrients will reduce the effectiveness

It's not low pH nutrients, it's specific types of nutrients that will make plants release of hydrogen ions or exchange hydroxyl ions that then changes the pH of the substrate.

 

[FelipeBlu]

I think we’re on the same page Shed.

 

[InTheShed]

I just wanted to clarify the language.

 

[Marzbadrock]

I think some good old fashion side by side experiments need done.

 

[Amy Gardner]

indicated that but it may have been too subtle.

words on pages can suck sometimes but only briefly,

Wish I had the room for science.

I wish you did too

type of nitrogen in your fertilizer will determine whether your pH rises or falls, along with the raising tendency of high alkaline water

it's specific types of nutrients that will make plants release of hydrogen ions or exchange hydroxyl ions that then changes the pH of the substrate.

Perfect So I’m suggesting that what you want, then, is a nute line that works to engage the plant in all the right ways for using the particular chemical balance said nute line provides in soil.

Do any nutrient companies claim to do anything like this? :curious:

 

[InTheShed]

words on pages can suck sometimes but only briefly,
I wish you did too
Perfect So I’m suggesting that what you want, then, is a nute line that works to engage the plant in all the right ways for using the particular chemical balance said nute line provides in soil.
Do any nutrient companies claim to do anything like this? :curious:

I think it would be difficult to formulate given the variation in water alkalinity, as well as differences in substrates when they are making nutes for coco/hydro/soil/soil-less. I mean MegaCrop can't even figure out which NPK formula they want to go with (three different ratios over the last three months!).