Soil pH Experiment

As a new grower and new to the forum I have been reading everything that is available and learning a great deal. One of the main things that has really gotten my attention is soil and water pH.

A few days ago I did a little experiment just to solidify some of the information that I have gleaned thus far in my first grow. I am using a commercial soil called “Gardener’s Gold”. I mix 3 parts soil to 1 part pure worm castings even though the soil already contains worm castings, bat guano, and several other ingredients. I had some issues with pH earlier and got them corrected.

Now to the experiment. First I created a slurry with just the soil and water adjusted to ph 7.0. The slurry tested at 7.1. Next I did the same test with the additional worm castings in the mix. The slurry tested a 7.4 - wow, I was surprised.
I then added a small amount of ammonium sulphate to the mix and saw a small drop (7.2) in pH but did not expect much.

Conclusion: Test the pH of the final mix as anything that you do to your soil and your water may affect pH and it is not necessarily obvious what the impact on pH will be. Test it!

I have a great soil recipe from @garrigan62 that I will mix up but I will also use what I have being mindful of pH. My first grow is doing well despite the pH issues that I have dealt with so there is something about it that is working.

My next experiment, in a few weeks, will be to grow sets of clones giving each clone in a set different water, raw from before softener w/o pH adjustment, after water softener w/o pH adjustment, and finally water before softener and pH adjusted (runoff at 6.5). All of this to determine just how sensitive the plants are to the variables.
@Niala @Countryboyjvd1971 @ReMoLu @Flyr @raustin @Donaldj @dbrn32 @highcountrygal @timmyv324


Cool! Pretty sure he incorporates dolomite lime into his mix. Which should buffer the ph some. Not sure how that will play into your experiments, but something to keep in mind.


Very interesting. You’re a mad scientist! :wink:

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For science!

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Actual scientists would take exception as I am only an aging electrical engineer.:rofl:


I wish you could be awarded a Nobel prize for your cannascience exploits

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