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How important is ph really?

420peace

New member
When it comes to growing weed, does anyone just ignore pH and succeed anyway?

Is it true that incorrect pH causes nutrient deficiencies?
 
Orggrwr is spot on. Soil tends to buffer itself around pH 7, but veggie gardeners will physically ammend their soul pH to match that sweet spot. Correct pH is essential to your grow. IMO, not checking pH is simply introducing something to go wrong. My coco grows ALWAYS have pH managed 5.8 to 6.2.
Look on GWE or the net for a chart of pH ranges and micronutrient accessability. That will help explain why. 😎
 
I grow in coco/perlite. PH is critical for me, so is EC and both cannot be ignored. I'm a little envious of the soil growers who never worry about PH. :cool:

Yes. It is true that incorrect PH does cause deficiencies. But it does that by creating nutrient lockout. The nutrient might be present but the plant cannot take it up because the PH is out of range. I recently read where improper PH is the most common cause of MJ plant problems.
 
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Living soil tends to self regulate pH or so I am told. I use coco/p and if the pH is off, you have problems. Without getting to technical, the pH changes the ionization of molecules and therefore the solubility and the plant's ability to absorb and use the nutrient. You can have all the essential nutrients present but if the plant can not access and use them, nothing works the way it needs to.
 
I am a hybrid soil grower and ph is important to me. Allotrope says I'm a closet coco grower and that's somewhat true. I think it's important to at least know what the ph of your water source is. I use tap water and was surprised that the ph was in the low 7s. I just expected it to be a little lower
 
Can we or should we really rely on our PH pen calibration w/o running a quantitative verified control after calibration and with each time the pen is used? In a regulated laboratory setting just calibration alone wouldn't fly! There is a reason for that. A calibration can be way off w/o use realizing it, thus the control. So, if you think your ph pen calibration is gospel then you might think again, it could be off more than you like or want to accept
 
This is also true for the ph strips. W/o running a verified control each time you use them then how do you know the strips are working correctly?
 
One thing about using instruments like the ph pen. You could test a sample on a given day then test that same sample with the same pen the next day and get a result that is 10% different. In most regulated labs a 10% deviation is acceptable based on many factors that I won't get into. Just an FYI
 
This is more for newer growers, but I'd like ckbrew and chipmunk to verify this post. (BTW, ok if I'm wrong). In my limited formal science education, I learned that pH is logarithmic, e.g. pH 8.0 is 10 times more alkaline than pH 7.0, not 1 times. A 10% increase, say to 7.1 is about a 26% decrease in acidity (H+, 10^.1 = ~1.26). The math aside, small pH changes mean big differences in the ability of micronutrients to ionize to a plant absorbable form. This is why I keep my coco pH 5.8 to 6.2., which they can handle.
 
Allotrope you are correct about the pH scale. It is indeed a logarithmic scale. pH 6 is 10 times pH 7, pH 5 is 100 time pH 7 etc.
 
Yes, you are correct. Let's try it this way. You say you keep your ph range between 5.8-6.2. How do you know your ph pen is giving you an accurate number when you have nothing to prove the pens calibration worked? The pen says ok the calibration worked! We can't prove that w/o testing a known control against the calibration. If I have a verified quantitated control to test at the same time as the unknown and the control is in range, then I can assume my unknown is accurate. We just calibrate and hope its accurate enough
 
I have an Apera ph pen. What I do is test a different buffer solution and compare the reading to the acceptable benchmarks published from Apera. That's my way to get control data that proves my ph pen was calibrated accurately
 
I guess w/o a known control the PH calibration isn't worth much. Am I understanding that correctly? What if you have two or three PH meters, all calibrated in the same solution, all read the same when PH is measured? How would one know they are accurate? Are we talking lab results or testing PH in the grow room?
 
I'd like ckbrew and chipmunk to verify this post. (BTW, ok if I'm wrong). In my limited formal science education, I learned that pH is logarithmic, e.g. pH 8.0 is 10 times more alkaline than pH 7.0, not 1 times. A 10% increase, say to 7.1 is about a 26% decrease in acidity (H+, 10^.1 = ~1.26). The math aside, small pH changes mean big differences in the ability of micronutrients to ionize to a plant absorbable form. This is why I keep my coco pH 5.8 to 6.2., which they can handle.
 
This is also true for the ph strips. W/o running a verified control each time you use them then how do you know the strips are working correctly?
It depends on what the process is that needs to be tested. If I am testing a buffer solution addative for intravenous amphotericin B infusion I would need an accurate and verified pH meter. In the garden the strips tell the story with plenty of accuracy. There is also redundancy testing. If the solution being made is the same formula as yesterday and the test is the same that is verification. When the formula changes and then the pH correction needed changes that is also validation. From reading this board for several years now, it is very frequent that when someone has a pH problem it can be traced back to a pH pen that has either not in calibration or has just drifted away from reality. Strips are easy.
 
That is exactly why I do this type of quality assurance/control on my pen. It just makes me feel better about my ph results, especially when I'm trying to diagnose a sick plant. I stopped doing strips when I got the cataracts and decided then that I liked the pen better. Do what you're comfortable with. I just wanted folks to beware the pen, it can bite you and you won't realize it till later
 
Yes. Chip is correct. Pens can bite you. My first one failed a couple of years ago and my plants were growing slowly. Got a new pen, adjusted the pH - et voila, happy plants.
 
I went thru 3 of the cheap $10 pens in less than 2 years. They'd drift, take forever to stabilize, then not calibrate at all. I bought a Apera pH60 about 4 years ago and never looked back. Stable pH in less than 10 seconds, never more than 0.05 off of all 3 cal stds, easy to read and calibrate. Make sure to buy the calibrate stds and storage solution. They don't come with much. Never store in water.
 
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"How important is pH really?"​

Think of it this way. You have a heavy door that weighs 2000# and it rests perfectly balanced on a hinge so that one person can easily swing open and close the door. The hinge is the pH. Sitting there barely noticeable happily doing it's job to make everything work. If the hinge fails the door stops moving easily, makes bad sounds, then if left uncorrected, as things get worse the door comes crashing down causing all kinds of chaos. That is how important pH is.
 
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