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Adjusting your pH when growing in soil damaging your plants!


New Member
Hello! I have some Problems with my Seedlings Vege Day 10. this is the first Time i have this Problems in this Young Age i dont know what i doing Wrong mybe the PH is Wrong with 6.2??? I using Light Mix Soil and i put my Water with 8.1 PH down to 6.2 my Plants are very Lime Green and looking not 100% Healthy.. Whats going on? thx



New Member
I have a question.my tap water ph is usually 7.5 or somewhere around there,after I put my Fox Farm nutrients in it takes it down to high 5 so I use ph up to get it to 6.5..the hole grow my runoff ph has been right at 6.5..now I'm in week 4 of flower my runoff keeps going up..last week it was 6.6 and today when I waterd it was 6.7...can someone please tell me if runoff ph is a must or should I just ph my nutrient water


Well-Known Member
Interesting topic. I think someone once told me to think of using chemical fertilizers as if you were growing hydroponically in a solution of dirt.

I always adjusted the pH of my water even if I was doing plain because my to water would be in the 8-9 range. I noticed fertilizer always dropped the pH quite a bit and I'd usually have to use pH up to raise it to 6.5

I would use probiotics too and noticed they're very acidic when in solution with nutrients, in plain water they were almost straight acid. I used a mix because I figured there were organics in the soil the bacteria would break down for the plant and leave more food than just the bottle nutes. So when I would drench with a tea I would not pH adjust.


New Member
hi every 1 .i have some plants into 43 days flower just come into a problam my ph run off is 7.8 when i go in every morning i adjust ph down to 5.9 i goin the next morning its at around 7.8 should i be concerned or just keep adding ph down every morning there healthy thoe i think lol.some say there a sativa with 4 weeks to go.


New Member
Dude, for the love of God, Allah, Jehova, Zeus, Mother Eart etc. Can you PLEASE use at least SOME punctuation marks in your future threads? Although most of your information rings true, the whole thread is basically just one long run on sentence. This can take away from all of the good information that you're giving us; some people may be confused as to when one thought ends and the next begins. If you don't let the reader in on it you may lose them altogether. Writing a thread and texting seem to have merged into one. Let's all try to have some pride in HOW we write as well as What we write; after all, it is a reflection of ourselves.


Well-Known Member
I agree that you don't need to adjust pH of plain water since it is (or should be!) unbuffered but I know when I add nutes (using FF primarily) the pH goes down to about 4.5 which is pretty acidic. My first grow I was using crappy ph paper to check and I am sure I did not adjust pH of nutes above about 5 or 5.5. Second grow I got a pH meter and adjusted nutes up to about 6.5 or so and my plants did a lot better. Could just be more experience on my part in general but I think even in soil the pH of nute solutions should be adjusted at least up to 6....
dam, how much FF you use to make solution of 4.5?? I have used FF and if it's going that low, you're using to much.


New Member
Here is my take on pH:

In soil, the pH needs to stay around 6.5 for best results.
If you are growing 100% organically, having the pH at 6.5 to 6.8 is VERY VERY important because not only are the necessary nutrients all available to your plants at that pH in soil, but microbial activity that is necessary for organic matter breakdown needs to be close to 7. A truly organic soil using only 100% organic soil amendments will always drift towards 7 or just below it because this is where the soil microbes like it best and if your soil is biologically healthy, then it will adjust itself due to the microbial activity. that is the pH they like and they will help to change and regulate it.

If you are using chemical nutrients such as my 3 part in soil, or fox farms for that matter, then your nutrient solution will most likely be acidic. When mixing my 3 part at 10 ml/gallon of Grow, BLOOM, Micro, the pH will roughly be about 5.5 depending on your water profile. The soil that I have used always has a pH of about 7.2 and when I feed, the pH drops to about 6.5 which is what I want so I don't use any pH UP.

Now, If you are feeding with chemical nutrients and they are causing your soil pH to drop too far from 6.5 for whatever reason (maybe your soil has a starting pH of 6.5 and adding a nutrient solution that is 5.5 causes it to drop to 6.0), then I would use pH up or Down to adjust your nutrient solution so that your soil environment will be at 6.5. IN true 100% organics this is rarely necessarry UNLESS, your soil has too much lime in it for example or your water is extremely hard for whatever reason has a high pH and is causing your pH of the soil to rise out of the acceptable range.

I know a very large grower in Oregon who's water out of the tap was 8.5. Her soil started at about a pH of 7.5 and she never adjusted the pH of her nute solution. After some time, the pH of her soil was close to 8.0 and she was having some serious micronutrient lockout problems. Getting a RO filter, a good flush, and adjusting the pH of her nutrient solution fixed all of her problems.

Basically, what I am trying to say is that you need to keep your soil pH at 6.5. If what you are feeding your plants is causing it to move too far from that number, then buffer your nutrients so that your soil will stay at 6.5

If you are growing organically, pH adjustment is rarely a problem due to microbial activity.

If your soil is shitty and started out with a pH of 8.0 for example, then you will most likely have issues of pH drift throughout your entire grow since there is something in your soil causing the pH to want to drift up. Same goes for soil that starts out with a pH that is too low. ESPECIALLY if you are using chemical nutrients. Who cares about microbial activity when using chemicals since the nutes are already all immediately available to the plants, right?

From a nutrient manufacturer's perspective, I also have to drop the pH of my nutrients to 4.0 or below to make them stable and to keep crap from growing in them. Even most 100% organic products have a very low ph to begin with. Take Alaska Fish Fertilizer. The only way that it is able to keep on store shelves is for the manufacturers to drop the pH below 4.0 which kills the enzymes used to digest the fish. They use phosphoric acid to drop the pH. If they did not do this, the bottles would explode on the shelves. Some products, even some organics, have a starting pH of between 2-4 and sometimes these need pH adjustment before feeding...sometimes.

Main thing is to keep the pH of SOIL at 6.5 and DO NOT let it drift too far from that value no matter what.

My 2 cents....hope this helps :)
THANK YOU! I was reading this thread and just cringed the whole time. PH is one of the MOST important parts of growing any plant. My water comes out at around an 8, if I didn't adjust down to a 6 to 6.5 my plants would be hurting. I actually went and created an account just to let you know, THANK YOU! It is hard enough to find correct information from the MJ community, it is nice to see some people research and educate themselves.


New Member
Not sure if you figured it out or not, but you should not water daily if you are using soil, it is hard to tell from the pics. For a PH that high you would want to add some sulphur, there are guides online (How to Adjust Soil pH for Your Garden - dummies) that can help you to figure out how much to add, it was the first thing that came up from Google.

From looking at your pics, I have a few other ideas, and this might be opinion over fact, but just my two cents. #1, trellising and trimming are your friend. I can tell that you probably dont have a ton of light reaching the lower branches, which is very common, remember the 3 node rule for trimming. You have buds on there that after 40 days should be 5 times bigger than they are, I notice a lot of popcorning from low light, low nutes and when trimming is lacking.

I'd also recommend way more Potassium and Phosphorous as your buds look very small. Obviously dont overdo it and make sure to do a 2 to 4 week water/molasses flush. Also, it looks like your plants were 'sleeping,' using a flash on a camera is not a good idea. It most likely wont cause Herms, but if you did it multiple times you could get them to herm that way.

Hope this helped!


I think this thread shows how many different ways folks grow with great results. The best research is in growing and experimenting. I've grown outdoors since the 70's. I never PH'ed anything. I grew indoors for the first time in the 90's one time with great results, no PH'ing. I been indoors constant now for maybe 5 years' The first year indoors I went overboard, PH up, PH down. I had constant issues. By the way I was using FFOF and still do. My nest run I used the same nutes, didn't even check the PH of anything and I've been doing that since. I've just started to let the soil buffer like it is made to do. So with my experience, I do better by not PH'ing anything, as long as I use FFOF and maybe a little lime. This shouldn't cause an argument, it should cause a debate at best. There are many different ways to grow this wonderful plant.


Well-Known Member
I'm using ffof as well. Maybe I'll try not phing next grow and see what happens. Good stuff
I did zero phing with my soil grows. If your in a different medium then pH is necessary, but it seems that soils have buffering. My soil is mineralized so that may be different compared to a bag of ffof.

Here is a test result of non-ph'd Sour Diesel.



New Member
The misinformation passed off as fact in this thread is very horrible. And very detrimental. "Don't adjust your pH no matter what in soil"???? Seriously? You people realize not every person's water is the same? Right?!? I ran a grow without adjusting pH in my water and my runoff was 5.6! Should I keep not adjusting my water? Even though there were sure signs of nutrient deficiency in my plants? Or should I treat my water so that my plants end up getting the nutrients I'm trying to ensure they receive? If I were to go by the OP's method my plants would surely die.

Be Irie

Nug of the Year: 2009 - Plant of the Month: Aug & Sept 2008, Dec 2008, Jan 2009 - Member of the Month: Feb 2009 - Nug of the Month: May 2008, Jan & Feb 2009, Nov 2012
Ok, there seems to have been a bit of confusion here because the title says soil and yet when he is talking about it in his first post you can see he is talking about organic growing. If you are growing organically in soil then there is no need to PH your feedings but you do have to make sure your soil stays in range. If you are using FF or similar then you DO need to PH your solutions/feedings.... I don't think people are purposely giving misinformation, just think it was a misunderstanding that got out of control.


New Member
How's it going? I know this thread is super old, but I just have been running into some issues all the sudden and I think it has to do with my soil, anyways, I just need some help on how to even test the Ph in my soil, or test it after adding the nutes, thank you! Check out my journal of possible


Well-Known Member
Re: Adjusting your PH when growing in soil Damaging your plants!!!!

Agree 100% on the ph of soil . . it's usually ok as it comes, even if u just dig up a hunk outa ya back yard. . .It's dirt, dope is a weed. . .it'll grow. stick half an inch / 10mm of pea gravel in the bottom of ya container, fill with dirt and you're away. No need for too much in the way of fancy (read fucken expensive) addins, and Roberts your mothers My firft week of
thanks BPN and icemud for input

so i stand corrected that wen feeding with chemical fertilizers in soil it is ok to adjust ur nutrient solution before feeding if nessecary (thanks bpn for the guidance) but a good point that i was making stands true is that to many new soil gardeners could be adjusting to the rong ph or even adjusting when theres no need to because they dont check there run off or soil for the ph of the actual soil in the beginning to know wot ph ur aiming for to hit the right ph they just adjust there solution to 6.5 and think there done wen they need to be checking wot the ph of there actual soil is first to know wot ph of nutrient ur aiming for to balance things out
This has been an incredibly informative thread for a first time soil grower. Sadly prior to reading this, I gave my several week old clones their first WEAK 1/2ml /gal dose of Roots Organics buddha grow nutrient solution. I'm growing in FF OS soil and using RO water. I foolishly ph corrected my solution to 6.5. So, I'm under the impression that I can just mix my nutes and then feed? Did I cause my little clones some harm? Prior to this they were looking great. I will have pics soon in my journal. Thanks to all who contributed in this thread!!!!!
My first week with clones my PH In My water was 7.5 out of tap. RO Water..... I am using Great Lakes Water Only Soil . I started to notice Stalks Turning Red.. So I ran out an Bought a BLUELAB Duel PH Reader. HOLY CRAP $$$ 298.78 SO then I adjusted my h20 RO P.H To 6.5. You can clearly see the green stalk growing After I adjusted The P.H to 6.5..... Then 2 weeks after that I wanted to add a light Tea." Plant Earth" Tea compost.. 60 ml to A Gallon.. That stuff is ph to your h20.. Fed my Veg.. They Flourished.... So I know my strains like 6.5 ph RO Water.. I did make the mistake, For my first feed in the flip I PH my water before I added The 15 ml to a gallon of Mother earth Sugar Load.. 60 ml to a Gallon Planet Earth Tea.. And 7 ML to a gallon of Advanced Nuitrents BUD IGNITOR... The PH Dropped to 4.8.. I for some reason a light went off "STOP" thought I better check the PH in the middel of feeding. Something just Popped in My Head..... I then quickly Made fresh feed.. PH'ing the feed after adding all of my Nutrients.. I did" well" I thought I better flush the ones I fed with RO 6.5 NO nuts water.. So I will lat ya know how the look in a few days... GOOD LUCk.. And from my Newbie Ass I know I need I need to PH My h2o. Everyone is different.. All of your ladies are different.. On;y you know if they like what you doing to them or not. I have 33 going right now. And its my first grow. 11 Ladies Day 7 of Flip... 8 That are vegging... 3 lady Clones that are 8 day old.... And 10 Seedlings.. They are very stong .. I should know.. Because I dropped a 2 week clone on the floor bare rooted, it also was double watered. It Shriveled up to the size of a half Dollar.. Everyone told me to throw it out. " HELL NAW" . Lots of love in care with a couple trans plates from 1 to 3 gallon pot.. Now she is thriving... I will use her for a Mother Plant... Good Luck


Well-Known Member
As I understand it,
Haha. You don't need to touch water unless you have hard water. Then organically drop it to near
Yep 6.5
Then use with understanding of the impact certain"charge" feeding and minerals can affect the ph. But that's the art of making a no til soil mix.
My soil mix is either,and most probably. Chronicly over charged with no balance or understanding, unbuffered or my girls have thrips. Neem oil coming to settle the diagnosis. So what do I know.
Oh no til. Just water, which is ph 7 when clean. No?
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