Forgot to adjust my pH

So I forgot to adjust my pH before I fed my plants. I’m growing in ffof soil and the pH going in was 5.2. What should I do, flush with 6.2 water and then feed again with correct pH feed. Thank you for any advice.

A one-off isn’t going to hurt the plant, just make you that you have pH trending in the right direction when you feed going forward.

There is no need to flush for a one time issue like that.


Thank you @MidwestGuy

Agreed. And in soils like hfof, to reinforce what was just said. Within the acceptable range you’ll be fine. Especially if you use someone kind of rhizo booster. My soil girls get fed anywhere from 5-7 without adjustments. Your soil has dolomite and oyster shells along with some rhizo bacteria already. All helping keep pH and uptake normally more dependant on pH. In control/check. The lines can handle acidity better than base. Of course. It’s when you get into 9s and above it seems a more prevalent problem in these soils. Since that’s going in the same direction of the lime. So it is no longer helping.

Better low than high. Generally. Unless the girls are feeding heavy. Then they can eat so fast it plumits…

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While water pH is important, it is the soil that affects the plant’s ability to take up the nutrients provided.

I recommend you check the pH of your soil or other grow medium. It’s very easy to do:

I checked the soil ph, I think I’m good. Thank y’all for the advice, I really appreciate it.

I’ve read you don’t have to ph your water if you’re in soil.
Is this not correct?

The only thing that is good for is taking temps. Soil slurry or runoff is only way using pH meter. I have one that also does moisture. When I used soil I would sometimes use it. I cut the pH probe off

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No, this is incorrect. Proper pH is required for all grow mediums.

You may have read that you don’t have to pH distilled or RO water when no nutrients are added. It is not necessary to pH “pure” water, as pure water does not have a pH.


Hey MidwestGuy, what you said makes sense, but see the below. I don’t mean to argue with you, but this is what I was referring to.

How to Adjust pH When Growing Organic Cannabis
Question: What’s the Best Way to Adjust pH If I’m Growing in Organic Soil?

How do I manage the pH of my soil when growing organically?

Young marijuana plant is loving lifeMore info: I’ve heard that many pH control kits can kill beneficial bacteria in the soil.

I was watering my cannabis plants tonight, and I mixed in a half strength dose of bloom nutes. So I test the PH and it is right in range, about 6.5. When I tested the runoff, it was really acidic at around 5.5.

What am I doing wrong, and how do I correct pH in my organic soil without hurting the micro-organisms the help the roots?


1.) Usually You Don’t Need to Worry About pH When Growing Cannabis With Organic Soil

As long as you’re starting with a good water source, usually you don’t have to think too much about pH during your grow.

When growing cannabis in organic soil, you usually don’t need to adjust pH, but if you do you want to use natural sources of PH Up and PH Down

However, when growing cannabis in organic soil, some of the most important things happen before you even germinate your plants. The more effort you put into starting with great organic super soil, the less you’ll have to worry about during the actual grow itself. If you’ve set things up properly, pH won’t be a problem for you!

Organic may be a different. I’m not an organic grower, so I can’t comment.

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@MidwestGuy gave you the answer and here is an example

This is day 69 in the life of these poor amnesia haze autos. Grown in fox farm ocean forest soil with FF Trio of nutrients. I did not own a pH or TDS meter two weeks prior to these photos. They are evidence of that fact. I was poisoning them. The one on the bottom right was nute burned to oblivion. The other three’s pH was so messed up they could not take in any of the nutrients I gave them. This was after I flushed several times and tried to reset pH of soil. Eventually the three pulled through. It was not pretty but a very good learning experience because forum members and moderators saved my bacon.

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Thanks Beardless for this real life example. I’m just trying to learn, there seems to be so much conflicting information out there. I read somewhere else that soil buffers the ph. My experience is limited to one grow, on my 2nd grow I intend on using FFOF. Do you think it’s ok to use swimming pool ph? I used them on my first grow and they seemed to work fine.

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I do not have an answer based on science or chemical knowledge but would ask why would you ever want to risk your plants or your health. Products made specifically to lower or increase pH water given to cannabis is readily available and not very expensive. I have used advanced nutrients pH UP and DOWN. Also General Hydroponics.
I do not know the differences between, for example, the acids used in pools like muriatic, nitric acids. And phosphoric acid used in AN pH Down.

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Better safe than sorry, I won’t use it next time. But like I said I used it before with no apparent negative effects.

Yeah that’s something I’ve heard on forums and from many growers for a long time.

Depends on your water, if you have 7.0 ph (or close) water coming out the tap then you don’t really need to ph it.

I’ve grown in soil (in pots) without ph’ing the water, plants lived, just weren’t the healthiest looking girls in late flower but they did make it to harvest, lots of ph lockout going on at the end though. My tap water sucks, near 500 ppm and a ph of 8.2 with lots of sodium.

I’ve also grown in the ground without ph’ing the water and they did much better than plants in pots. The Earth takes care of ph much better than pots and peat based potting soil.


You make quality posts @Hellraiser


With that said I guess I will absolutely ph my water up and down between 6 and 7.
Thanks Hellraiser and the rest of you.