How long does it take to correct soil PH

So currently there is a shortage in my country of the compost I normally use. Ever since I had to change my growing medium I had to amend differently. Unfortunately my plants have been suffering since the change and I’ve only gotten my ph tester today!

I’ve been flushing and trying to correct PH over night since its been low as 4.19. By adding the limestone, would I see an immediate PH change?

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Probably not what you are looking for. You may see small improvement relatively quickly, but generally takes a while.

Hopefully my plant don’t die as it is in Flowering. I guess it’s going to get worse before it gets better.

From the research I’ve done, baking soda may be your solution. It’s not as long lasting of a solution, like lime, but it shows results more quickly.

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Will try this and see

Long term use of baking soda is not advised; it will harm the plant.

Dolomite lime is about the only thing I can think of to bring PH up.

What about swapping out new soil? Or at this point just keep adding lime? And if so for the lime how often? Once pots get dry apply some more?

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Might not be a bad policy too because plant looks like it could be pot bound. If so, dying root mass will cause PH to drop too. Potting up into some more appropriate media might work.

That’s why I suggested it as a quick solution.

Had a similar issue.

Pot looks small, increase by a couple gallons.

I had a ph runoff at 5.8 whrn feeding at 6.6, plant looked sad and like the one in this pic.

In a 3gallon fabric pot i flushed with 8gallons of 7.7 tap with ppm at 306. Let tap water sit a while and evaporate all perservatives and chlorine.
Ppms off the jump were ±2300 minus origional 306 so arpund 2k. Nut locknout for sure! Half way thru flush ph was at 6.2 and ppm at 1500-306. Final reading eas at 6.6ph and 550 ppm.

Before upgrading to 7gal for flower cycle ill flush the soil ill be potting with, i checked soil and runoff is at 5.6ph. So ill flush with high ph water til it reads around 6.5 to 6.8 then ill transplant from flushed three gal to ph’d 7gal.

From there i will ph all feed and water around 6.6 or so. Its a lot of work in the begining hopefully will save some time , stress and especially quality of harvest.

Any other pointers will be greatly appreciated

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Thank you for the info. Going forward, now that I have my meters I will be ensuring things are on point. Quick question though; why did you say

Should small ppm to big suggest that the plant is not absorbing Nut ? I am still trying to get a grasp on these meters so any help is appreciated

How do you bring ph down and keep it there?

Ppm from runoff water was 2338 to be exact. 306 was the origional ppm of my tap water that i fushed with. So the ±2300 - 306 put my soil ppms at around 2k.

Having that much ppm in a 3 gallon bag in late veg is pretty high. I like to be around 800-900 if possible thru end of veg.

High ppm in soil means plants arent uptaking nutes and are Locked Out or Nute Locked.

I water in nutes at 800ppm with RO water at 0ppm for a true + - 800ppms, if the runoff water is over 1k ppm a week later something is wrong.

Or high salts to begin with. Running a test on something like Miracle Gro will give you double those numbers after using for 2 months and the PH will be 3. So depends on what is stacked into that soil. I suspect that the act of removing salts is what is responsible for your PH adjustment.

2,000 ppm in soil–like FFOF is fine as soil buffers the plants roots differently than in coco.

Same as my receipe above for raising except you use liw ph flush.

Yours is high, example 7.2 or so and want target of 6.5 to 6.8 in a 3hal pot. Multiply your gpot size by 3 and that how many gallons to use to flush.

If 7.2 for ex, iwould ph flush water at 6ph and start flooding plant allowing all runoff to drain. Check ph levels 3rd way thru to see if any changes and how much. If half way ther keep going as until readings are satisfactory.

If not, drop ph of flush water lower and proceed to flush, check ph runoff halfway thru to see any changes.

Best time imo is morning so plant cann absorb wster, if outdoor sun and wind help evaporate flush. If indoor pkenty of air flo and if possible some small fans low speed on the pots not the leqves or plant itself, avoid windburn.

Once ph in soil is stable you shoild check runoff once a week. And water or feed in at ph adjusted levels to compensate off ph levels.

I bought a expensive ph meter cause ibwas tired of replacinf cheap ones at $15 a pop. I got one at 60bucks and trust it as i compared to the box of old meters. It read along the two i trusted of 8 meters.

Invest in a good ph meter is king!

I’m not sure I know what you mean to flush I’m new

Flush, to run non nutrient as plain as possible ph’d water thru the medium (soil) to either lower the salt (nutrient)content that has accumulated or to raise or lower ph of soil.

Is this before you plant or after

Ph flush can be done before planting to have correct ph in soil befoe planting(recommended) and during all growth cycles.

Nute flush is only after planting and adding nutrients to feed the plant with. If you have added to much nutrients the plants could burn leaves or create deficiencies or over abundance of nutrients which is bad for plant. If plant has bad ph it will not absorb nutes and nutes will remain in soil creating a “Hot medium” which is bad.