Soil Ph Slurry Test - Step By Step With Photos

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PipeCarver

PipeCarver

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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!
Okay, great but what are you looking for from a slurry test that a proper runoff test won't give you? We're not talking about the 1/100 decimal point to be accurate.

If you get a runoff test that says 5.35 then you know you have a low ph problem. A slurry test may be more accurate by giving you a 5.28 or the other side5.43 Either way it doesn't matter you're going to take the same measures to get your ph up.

It's highly unlikely you'll take a runoff test reading of 5.3 and a slurry test of 7.5. Both readings will be close enough so that the difference is negligible to the results.

I don't care what you probe into the soil unless you're growing turnips you'll damage roots, even if you some how don't damage any does the sample give you different results from a runoff test?
 
Moshmen

Moshmen

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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!
Wish I seen this an hour ago ! Great tip will try next time
 
b8kd

b8kd

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Fantastic thread. Loads of information in these two pages of posts. Thank you all very much for providing this information. Sounds like I can probably do a slurry test now, while the plants are young, but as my plants roots start to completely fill out a container I may want to move to run off tests for pH. At a minimum I've learned to be very careful with my plants rootball. ;-) B8KD
 
b8kd

b8kd

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Fantastic thread. Loads of information in these two pages of posts. Thank you all very much for providing this information. Sounds like I can probably do a slurry test now, while the plants are young, but as my plants roots start to completely fill out a container I may want to move to run off tests for pH. At a minimum I've learned to be very careful with my plants rootball. ;-) B8KD

I went ahead and did the slurry test and more. The results will be very useful moving forward. All results are listed in my grow journal here:

 
Aqua Man

Aqua Man

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Can a slurry test be done on a organic grow after it has been amended to check for ppm?
I would not use ppm to measure nutrients for an organic grow. Typically organic nutrients can affect the ppm but will not accurately reflect on the availability. However if you keep records the ppm can show a trend as to if say nutrients are being depleted. This is mainly because while some compounds may be soluble and can affect ph they may not be available for uptake by the plants. So imo it's very unreliable to base nutrient availability on ppm with organics.
 
oldskol4evr

oldskol4evr

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Can a slurry test be done on a organic grow after it has been amended to check for ppm?
best way to get what your looking for is a tissue test,it will provide you with documented numbers if what and how much you plants are taking,if you just amended the soil recent ,a ppm test would be void,it takes quite some time for decomposting to come to play and have the full effect you seek,best tool is tissue sampling though,i know of the test for veggies,not sure about cannbis as of yet though,with vegtables it is very effective for next crop going in ,you will have results of what the last crop took from your soil and with rotation you can add back with difrent species of plants ,there for not using nothing but plants to reamend your soil,i plant corn then rotate beans in the plot to add back nitrogen,corn sucks it down along with plenty of water,the beans put it back,if you dig what i mean
 
b8kd

b8kd

93
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I would not use ppm to measure nutrients for an organic grow. Typically organic nutrients can affect the ppm but will not accurately reflect on the availability. However if you keep records the ppm can show a trend as to if say nutrients are being depleted. This is mainly because while some compounds may be soluble and can affect ph they may not be available for uptake by the plants. So imo it's very unreliable to base nutrient availability on ppm with organics.

Aqua Man - Are you saying ppm measurements should not be used for any type of measurement when using organic nutrients? Or are you stating don't use organic ppm for a specific measurement such as slurry test, run off, feeding (solution strength), etc? Please clarfiy.

I did notice that with Organic nutrients the run off is essentially useless, wildly high numbers after a period of time, and my assumption is the slurry test would be very high at this point too. I've been using an Earth Juice Primary Plant Tea Recipe for every watering (slightly modified, mix includes twelve items) for most of my grow. At this stage, week one flower, feedings are kept below 1250ppm. When I first found this thread, and did these tests, the numbers all seemed so interesting. They don't mean a whole lot to me anymore.......other than for feeding.

I've been using it to insure my feedings stay in the correct range based on my plants current growth stage (veg, pre-flower, flower, etc). It does give me a baseline with regard to knowing how hot my nutrient solution was the last time I watered and if I see some type of issue with the plants (overfeeding, etc), I've got a baseline that I've been working off of and can adjust accordingly before feeding again. Thanks, B8kd

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Aqua Man

Aqua Man

26,480
638
Aqua Man - Are you saying ppm measurements should not be used for any type of measurement when using organic nutrients? Or are you stating don't use organic ppm for a specific measurement such as slurry test, run off, feeding (solution strength), etc? Please clarfiy.

I did notice that with Organic nutrients the run off is essentially useless, wildly high numbers after a period of time, and my assumption is the slurry test would be very high at this point too. I've been using an Earth Juice Primary Plant Tea Recipe for every watering (slightly modified, mix includes twelve items) for most of my grow. At this stage, week one flower, feedings are kept below 1250ppm. When I first found this thread, and did these tests, the numbers all seemed so interesting. They don't mean a whole lot to me anymore.......other than for feeding.

I've been using it to insure my feedings stay in the correct range based on my plants current growth stage (veg, pre-flower, flower, etc). It does give me a baseline with regard to knowing how hot my nutrient solution was the last time I watered and if I see some type of issue with the plants (overfeeding, etc), I've got a baseline that I've been working off of and can adjust accordingly before feeding again. Thanks, B8kd

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Personally I would not use it for anything. Some may but I wouldn't. I would simply go back to what we did before ppm meters... Just read the plants
 
b8kd

b8kd

93
33
Personally I would not use it for anything. Some may but I wouldn't. I would simply go back to what we did before ppm meters... Just read the plants
Thanks for the response. Not sure that I’m quite to the “read the plants” experience level yet, with this being my first grow. I think I understand where you’re coming from though.

I’m actually kind of glad that I got exposed to the organics for this first go round. It’s caused some additional issues/hassles, that I’ve had to research, which ultimately helped me better understand “WHY” I’m doing what I do.

✌️ B8KD
 
Weeblek

Weeblek

61
18
So I see this is a very old posting, but for me it is new as of today and I cannot thank the dude who wrote it enough for teaching me how to do the Slurry Test. I am 3 weeks into my 1st indoor grow and my girls are looking great. But now I know that my pH Levels are right at perfect, so time for me to figure out what the heck is wrong. One thing I did that wasn't mentioned and that made it somewhat easier, was that I crushed the soil and stuff in my cups into a more fine powder consistency because when I did 1/2 dirt/water a few were so thick Idt I'd have been able to do the test. But as a powder the 1/2 was more than adequate. I also have my 6 giant straws labeled and ready for next time. Thanks to whoever had that suggestion. Anyways, again, I'm so glad that I found this thread because dude made it so much more simple than any other I came across. I was no longer intimidated thinking I'd screw it up. - WK
 

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