Lowering potted soil pH quickly

What strain, ILGM Strawberry cough

Method: Soil, FFOF. Starter nutrients were GH Flora Trio. Switched to Down to Earth dry organic on 4-16

Vessels: Pots- 5g fabric

PH of Water, Solution, 6.3-6.5

PPM/TDS or EC n/a


Light system…sf4000

Temps; no higher than 80, no lower than 70 all time

Humidity; between 40-50% All times

Ventilation system; don’t need

AC, central

Co2; don’t need

So my issue is pH in the soil. Was watering my girls last week and I believe my pH pen gave me a bad reading. I can almost eyeball how much ph up to use in my mix but this time was different. I put the normal amount in and the meter was reading pretty damn low so I added more. Just going from past experience with this ph up and how strong it is, I’m almost certain my girls were watered with ph above 8. Since that watering, the upper leaves on both Strawberry Cough plants have been drooping, only upper leaves. They droop really hard closer to lights out but overall droopy compared to when they were healthy. They also have interveinal chlorosis and an almost 3D look to the leaf itself. Also, New Growth is coming out skinny and pointed. Growth is still there but really really slow. What I believe is going on is zinc deficiency caused by high pH, almost 100% on that. Want to know how to lower pH in soil.
I know what most people would do is flush their plants but I have switched over to organic dry amendments recently and not sure if that will do any good. Any suggestions?? Thanks for the feedback in advance


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Here’s a couple pics to show what I’m talking about when I say New Growth is skinny and pointed

You could perform a soil slurry test, this will give you some insight of the soil ph

Hey thanks for the video @Dave101… wish I could do a slurry test but don’t think I’ll be able to. These plants have filled out their containers pretty well so it would be hard to dig out some soil under the surface, roots everywhere!. I also top dress with Dolomite lime. Do you think the lime will throw my reading off??

I’m no expert when it comes to Dolomite lime, but I believe it’s added to potting soils to raise the ph. Peat based potting soil tend to be more acidic, so lime is used to buffer the soils ph in the desired range. Problem is you don’t know your ph so your going at it blindfolded. Again I’m probably not the one to ask when it comes to Dolomite lime.

Yes you’re right @Dave101 … I use it to maintain a 6.5 pH in my medium. What I’m thinking I may do is just water with some 6.0 and wait for the lime to do its job. Was ready to send these girls into flower but I’m holding off now until this clears up…

Have you measured the PH of runoff water right after watering? If so, what is it? I grew in soil many years ago and remember PH in soil being pretty liberal with regards to what the girls could take before they stopped nute uptake. If you can get a turkey baster and gather enough runoff water to test - this will guide you :handshake:

And measure before so you know your baseline…

Hey @IKnowURider that’s not a good method for getting pH from soil. The water passes through the soil too fast to get a true reading. On top of that, I previously used synthetic nutrients with little to no runoff and I’m sure the water will pick up lots of those salts throwing the reading off even further. I’ve got a PH soil probe that’s giving me a 7 reading but I’m not sure how accurate this thing is. Probably the most accurate way would be a slurry test like @Dave101 suggested but my use of dolomite lime would render those readings useless. Bluelab has a way for me to find out the soil PH but that’s a $190 decision I haven’t made LOL

i’d ride it out :handshake: Probably depends on many variables - but I think you would need to water soil with bad PH for quite some time before you’d change the PH so much they stop taking nutes up. I always remind myself - it’s a weed.