Soil Ph Slurry Test - Step By Step With Photos

JWM2

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Knowing the pH of your growing medium is important from time to time. The soil pH slurry test is the easiest way of finding the true pH level of your soil based growing medium.

For this you'll need:

Step 1: Collect a soil sample.
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Step 2: Add distilled or RO water to your cup or container. Use a 1:1 or 1:2 ratio of soil to water.
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Step 3: Stir vigorously into a slurry. Stir for a few minutes.
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Step 4: Let it rest. Then stir again. Do this over the course of about 15-30 minutes. The longer the better.
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Step 5: Insert your pH meter into the slurry and read the results. You're done. That's the pH of your soil. You can also do this with your ppm / ec meter if you are interested in the conductivity value of your soil.
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never tried this but one question....where do you take the soil sample if you top dress weekly? I don’t want to disturb any roots or anything
 
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After the soil has dried on the surface, take your sample half way between the plant stem and edge of the pot. Push away any loose material. Using a small spoon, or your index finger, dig a small hole approximately 2 inches deep clearing away loose soil as you dig. Carefully take your sample from this area. You may disturb the roots a little but it shouldn't cause any adverse effect. If possible put the dirt back after the test.
 
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I have mentioned the OGCFam show. The latest series of video presentations are all about slurry tests.
Ya I checked out a couple of those and its must be nice to do a deep soil test with plants that don't grow roots like pot does, they dig in the soil nice and deep down 3-4" and grab some soil. Not a root disturbed or broken. iI there any video's you know of that show it done on pot plants or something with roots similar to pot plants?
 
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Well, it has been accomplished by many. Just carefully try it.
I did, that's why I'm bitching. I was encouraged to one so I did and got the same results doing a root damaging deep soil slurry test as I do with a runoff test within a couple of points. I get doing the test but to get a sample out of the center mass on pot plants roots are going to get damaged. Is it worth it when a runoff test gets very similar results. I'm not sold on it.
 
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I did, that's why I'm bitching. I was encouraged to one so I did and got the same results doing a root damaging deep soil slurry test as I do with a runoff test within a couple of points. I get doing the test but to get a sample out of the center mass on pot plants roots are going to get damaged. Is it worth it when a runoff test gets very similar results. I'm not sold on it.

I read an article about this by an agricultural soil tester and slurry is the most accurate way to test. It was about slurry vs. the expensive probe meters. And for testing farm, garden etc. soil it makes sense. For testing custom soil mixes it makes sense to me too. But checking and logging runoff is the standard of container gardening. And with pre bagged premium buffered potting soil i think chasing ph is a fools errand anyway.
 
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I read an article about this by an agricultural soil tester and slurry is the most accurate way to test. It was about slurry vs. the expensive probe meters. And for testing farm, garden etc. soil it makes sense. For testing custom soil mixes it makes sense to me too. But checking and logging runoff is the standard of container gardening. And with pre bagged premium buffered potting soil i think chasing ph is a fools errand anyway.
I have no doubt the slurry test is the most accurate method but do a couple of points really mater. If a runoff test gives you a 4.8 I think you can be pretty sure a slurry test will give you similar low results. Its not like your going to get a runoff result at 4.8 and a slurry test result at 5.8. I'm new at this soil testing but after my 1 time try to get soil from the pot I can see no possible way to do it without damaging roots and if a runoff test gets me in the ballpark then that seems to be the safest way. Checking and logging runoff throughout the grow like you said should prevent the drastic measure of doing a deep soil slurry test in the first place.

You know just talking it out with those of you guys here really helps me to get all this stuff straight. I've taken a lot more interest in my growing since I've been here. Reading these posts I've renewed enthusiasm with growing. Having to keep this secret for so long with no one to share my growing with stunted my growth. I wouldn't even visit sites like this for fear the man might track me down just for participating in this nefarious activity. I've spent more time in my grow room fixing, fiddling with things and improving my spaces environment since I started participating on site. Its also costing me more with new things I have to have or would really like just about everyday, wifes getting ticked off and wants to ban me from this site.lol goodluck with that I'm bigger than she is lol.
 
HI,

just discovered this method but when I use a ratio of 1:1(20g of Biobizz allmix soil mixed with 20g/ml RO water)i get moist soil no liquid what so ever....no way I can measure with my pen?

I used a 2:1 ratio water/soil with fresh bb allmix and i get 5.8 on the bag it says 6.6?? bad charge?

my pen is calibrated and very accurate been using it for quite some time now....no faults here
 
Great nice work! Now can you show us how to do a deep soil slurry test with plants that already have a root ball. How to do it without munching through roots is what I need to see please.
I know this is older but IU yse a SS drinking straw the wider the better.. and I wiggle push it down into soil give a twist and pull it out and tap the soil out into test container.. I pull from 3 places around plant and only use the bottom half of soil for testing to ensure a deep pull for test... then do the slurry test as described above! That how I do it and has worked so far!
 
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