should i really not bother with the ph??

[umbralindigo]

bigshrimp, I do not run 30 gal no tills, nor do I personally deem them practical for indoor situations usually. I do not pH, will not pH, and by all standards, if my water is going to need to be pH'ed I'm going to choose another water source. Hopefully from the sky. To me it's like seeing purple on your plant leaves and saying "o shit, I need some phosphorus quick", instead of saying "I wonder if my roots are cold?" Like science says, look for the most simple/obvious answer first.

I'd like to point out what microbeman has said before. As it was only conjecture, I need not apply this as fact. Over-fertilization can possibly lead to powdery mildew. In my own growing of vegetables and or anything else, I have noticed that too much foliar feeding and high nutrient base can lead to problems like powdery mildew, and heat and cold stress (that's my own assessment.)
I find that when I did use too many kelp teas and too many foliars (trying to combat PM), that it sort of invited it along also. As soon as I stopped all the extra feeding and only "fed" with compost "tea", I stopped seeing those problems. I can only assume that trying to mess with my pH would alter my biology in a similar way.
Also, eureka, a question, do you think that applying compost tea as a foliar have any benefits? How are the microbes actually being transferred through the plant tissue to then feed the plant? I originally thought it needed the root of the plant being "fed" to have this effect. As in a purely symbiotic relationship that the plant only gains benefit through its roots.

 

[bigshrimp]

how is lime better than humus? lately ive heard a lot of not so great things about lime, thats why so many people are switching to oyster shells?

Both lime and hummus have the capacity to buffer ph change. This is measured in CCE - Calcium Carbonate Equivalent. Some other substances like char and expanded clays also have this capacity.

Oyster shell is calcium carbonate - lime - it is used as a better alternative to Dolomite lime, which can lead to unbalanced Ca/Mg ratio when used alone.

[FONT=Arial, Helvetica, sans-serif]CC's 3-way lime mix based off Steve Soloman's 3-way lime mix.

1 part powdered dolomite
1 part agricultural gypsum
2 parts powdered oyster shell

1 to 2 tablespoons lime mix per gallon of peat moss...NOT soil mix. Or 1 cup per cubic foot of peat moss.[/FONT]

In peat based mixes with little humus liming is necessary. Peat becomes more acidic over time - adding proper amounts lime keeps this balanced at seven or so. Also providing calcium, magnesium, and mabye sulfur depending on your liming mix.

When you have a more diverse soil such as Gascanastans mix,
(peat,coco,leafmold, ewc, local topsoil, char, DE, epanded clays, etc..) liming becomes much less important for a few reasons.

First off there is just less peat to lime. On top of that there is the CCE of your diverse aeration amendments and of your humus. The combined CCE of those and other Ca rich amendments (fish bone meal, crab/crustation/shrimp meal, bone char) can significantly reduce your lime requirements.

And when you add healthy soil ecology to a diverse mix like that in large containers liming really becomes a minor consideration.

 

[bigshrimp]

Surf - Yes i did completely misunderstand you. I completely skipped the word 'besides' in your original post. lol

[FONT=Arial, Helvetica, sans-serif]If D.Cocks applies high pH water/nutes to his very acid Happy Frog the first few waterings, and it fixes the problem permanently as he says, why is liming better? -granger [/FONT]

Yea after his response i would agree, if its stabilizing fine later than just let it be. I thought he had to continuously add ph up the whole grow.

 

[DinosaurCocks]

happy frog is peat based, and as you mentioned peat gets more and more acidic over time, that is why im assuming my shop orders in bulk maybe 1 or 2 times a year and just stores it all, allowing it to become quite acidic, my shop is small, but has a huge building just for storing overhead...so that's my conclusion anyway since ive only heard of this issue from my friends buying the same soil i taught them with from the same store...

[FONT=Arial, Helvetica, sans-serif]No after his response i would agree, if its stabilizing fine later than just let it be. I thought he had to continuously add ph up the whole grow.[/FONT]

even my organic fertilizers say don't ph, organic soil will buffer itself somewhat. so as long as your water isn't grossly out of range it should be able to handle itself, at least that's how i understand it. my soil is grossly out of range when i buy it, so i counter that with my first few waterings way out of range in the opposite direction... i have found out the hard way that organic soil isn't going to be able to buffer quickly enough if it's as far out of range as mine, it takes about 4-6 weeks of my normal un-ph'd waterings to fix it, by then my leaves are a twisted mess and yield is cut by quite a bit...i know this because it took me a good month to find an organic ph up substitute when i first switched to organics and not something that was simply "natural" which could mean anything.

i wouldn't know the true numbers, but as long as you aren't grossly out of range ph testing shouldn't be necessary. plants in an organic garden can access nutrients at a greater range of ph's than chemically grown plants, and organic soil has the ability to buffer itself to an extent.

i don't think anybody could make an argument against checking ph...i mean it can't hurt...but it is kind of a pointless exercise i think... i suppose depending on what you are using to correct your ph though that could be argued against...some things are better than others...a buildup of certain minerals can make your soil extremely compact over time...

 

[Scrappy4]

For organic growers good compost is our ph regulator in conjunction with the plants, although I agree with Verdantgreen that high alkalinity water may cause problems more so than high ph water. Alkalinity is a measure of buffering levels against acids BTW hopefully this paper will light some of the dimmer bulbs lol

Soil Biology and pH by Jeff Lowenfels

The success of the AeroGarden, the first plug-and-grow aeroponic kitchen appliance, is testament to the fact that ordinary people do not understand the concept of pH and don't want to deal with it in their growing situations. Make it so you can practice hydroponics without this chemistry barrier and they will come, apparently.

Frankly, the concept of pH also confuses soil gardeners. Heck, the definition of pH was inadvertently reversed in my book "Teaming With Microbes: A Gardener's Guide to the Soil Food Web." (Yes, some readers noticed; I received two "you made a mistake" notes. But that's not as many as I thought I'd receive.) Fortunately, the mistake was corrected in time for the second printing.

In any case, soil gardeners have been told certain plants require acidic conditions- for example, rhododendrons and azaleas- or else they won't grow. The solution advocated by most experienced gardeners is not dissimilar from what a hydroponics grower would do: adjust the pH with chemicals, such as agricultural lime, to make the soil more alkaline. To make alkaline soil more acid, we are told to add sulfur. Because they are chemical changes, these solutions work for a short time. But to me pH is a biological matter.

A bit of quick pH review is in order (if only to make amends for the mistake in my book). You may remember that pH is a measure of the acidity or alkalinity of a solution on a scale of 1 to 14; 1 being most acidic and 14 being most alkaline. A more technical description is that pH is the measurement of the concentration of hydrogen ions, H+. If you have lots of H+, the pH is low, or acidic. If you have few of them, the pH is high, or alkaline.

If you are adding fertilizers and using chemicals, you are stuck in the chemical realm. Organic gardeners, soil food webbies in particular, realize that pH has more to do with biology than it does with chemistry. That's because of the way plant roots take up nutrients. Root hair surfaces are covered with positive electrical hydrogen cations. Think of these charges as ping-pong balls. If soil particles are small enough, their surfaces are covered by these ping-pong ball charges, both positive (cation) charges and negative (anion) charges. These cations are not limited to hydrogen; they also include calcium, potassium, sodium, magnesium, iron, and ammonium. All are important plant nutrients.

When a root encounters a clay or organic particle, it can exchange one of its hydrogen cation for another positive one from the particle. It can choose from calcium, potassium, sodium, magnesium, iron, ammonium and hydrogen, as these are all cations carried by clay and silt and are all, as luck would have it, major plant nutrients.

This is known, incidentally, as cation exchange capacity, or CEC. Sand and silt have low CECs, because they comprised of particles that are too large to hold electrical charges. This is why humus and clay are needed to make soil good. They are extremely small particles and can carry cations.

So, back to pH. Every time a plant root exchanges a hydrogen ion for a nutrient ion, it increases the concentration of hydrogen ions in solution. Thus, the pH goes down and things should become more acidic.

Ah, but things usually balance out because the positive cations on the root surface also attract negative charges. Here, hydroxy ions (OH-) are the exchange ping-pong balls, and addition of hydroxy ions lowers the concentration of hydrogen ions in the solution, and pH goes up.

I know this still sounds like chemistry and not biology. However, each plant has an optimum pH requirement. What soil growers need to know (and hydroponics growers don't) is that the type of bacteria and fungi attracted to a plant's rhizosphere by the plant's exudates has a lot to do with setting this optimal pH. Bacteria produce a slim that raises the pH, and fungi produce acids that lower the pH. Since the plant is in control of the biology it attracts, in a natural system, it is the plant that determines the pH, and not some chemistry teacher.

So, while you may forget the chemistry of pH, at least remember there is a biological side. Do no harm to it, and you shouldn't have to worry much about pH when you grow plants in soil. Moreover, the nutrient exchanges that occur above also have a lot to do with what kind of bacteria and fungi are attracted to the root zone as some like higher pH and others lower pH.