Soil pH testing - simplify please

[NCBear420]

So I've read a lot about soil pH testing......have a basic understanding.....just wondered if someone could clear some things up for me:

If I understand correctly, one should test the pH of the tap water before using, then re-test the water after you've added any fertilizers, test the pH of the actual soil, and lastly test the pH of the pot run-off ?? That's 4 things to test? Really- is all that necessary?

Do you correct the pH of your tested tap water, then readjust the pH after adding nutrients, so that it's always 6.5 ?

Do you rest the actual soil when it's pretty dry before watering, or measure it immediately after watering/fertilizing?

If anyone could simplify

 

[go4snypr]

Re: Soil pH testing......simplify please

test your water after adding nutrients. then correct to proper ph.. run proper ph water thru soil, and then test the run off of what comes out the bottom... if run off ph is out, you have to look at how to correct the medium...

 

[NCBear420]

Re: Soil pH testing......simplify please

Thank you go4snypr! Do you know off hand if a device made to measure soil pH will work to measure pH in a liquid (ie water, run-off, etc), or is there another type of device to measure ph of liquids??

 

[go4snypr]

Re: Soil pH testing......simplify please

I would suspect they are different devices, as I would not want to stick my ph probe into dirt. I dont really think people test the soil as much as you test the run off. If the run off is high, I would think you would flush the soil with a ph adjusted water until the runoff matches what your putting in, that is what I am doing, but I am not growing in dirt so I dont know if that applies. You may have to mix something into your dirt to get the ph down, I am not sure. Hopefully someone else will chime in on that.

 

[Fuzzy Duck]

Re: Soil pH testing......simplify please

Measuring run off is f@*ked up...

Some where in the last 20 years being involved in the horticulture trade, i seem to have missed the point of measuring PH value of run off after feeding plants in soil !

Assuming or well lets just most plants do well in a soil PH value of PH 6 to 7 where a large majority of nutrients are available & that is where the real chemistry is involved.... and not the PH corrected nutrient solution.

So i may ask how many people measure the run off after feeding their house plants, tomato plants or other veg's grown in soil... they do not !

I mean do you hear of farmers PH correcting water to water the crops... how do granule fertilizers work for example, like how the fuck do people who grow MJ out door in soil measure their run off ???


Run off is a load of bollocks



What it really boils down to is correct PH of soil to make nutrients available & that is all....



I might go into over feeding which may effect soil PH, nutrient lock outs etc but that would make this post long winded...

 

[go4snypr]

Re: Soil pH testing......simplify please

so your saying adjust the ph of the soil then?? and then keep water in same range??

 

[Fuzzy Duck]

Re: Soil pH testing......simplify please

Ye soil PH is the important part & ideally should be between PH 6 & 7 for soil/compost grows to which you may find that soil/compost has natural buffering effect and will return to its ambient PH value after several hours or so after watering/feeding...

Which can be observed with soil PH probe even a cheap thing like this you can monitor the change over several hours !

Helps to remove probe between testing as leaving these cheap probes in soil/compost for a prolonged time e.g many days in row buggers them up.


So water PH is really not that important for soil/compost grows... but only applied to hydroponic grows such as DWC, NFT & inert mediums such as perlite, rock wool, clay pebbles etc



Rain water is classed as soft water (mildly acidic) FACT, farmers and other growers most freak out when it rains as their plants are getting soft water (not PH corrected water) in their fields aka soil grown plants... so why do they PH correct their soil of the fields for growing.

PH of soil between regions and parts of world do change by the way...

 

[NCBear420]

Re: Soil pH testing......simplify please

Thanks Fuzzy Duck. Great graphic and simple explanation. My soil pH meter should arrive in a couple of days!

 

[Fuzzy Duck]

Re: Soil pH testing......simplify please

Thanks Fuzzy Duck. Great graphic and simple explanation. My soil pH meter should arrive in a couple of days!

Ya welcome & once you have observed the buffering nature of soil/compost over a 24 hour period you will more than likely not look back on measuring PH of run off !

After all run off is leached water as this picks up trace elements of what ever nutrients/fertilizer all ready in the soil & this will make new readings of PH or EC etc slightly off...

In less to the point of over watering with nutrients & finally the run off may read some where suitable... some what a waste of nutrients/water if you ask me ! even tho some hydro systems work on this basis with inert growing mediums aka hempy buckets for an example.



So sit back watch and observe the buffering effect

The only things i can think off which may effect PH value of soil over time is excessive feeding and very hard water or rain water !

But in the short term of growing MJ over 3 to 4 months indoors under lights its going to be hardly noticeable, in less reusing compost/soil more than a few times then amendments may be of practical use...

 

[chemo64]

Interesting. Thanks for the tip.