should I expect my PH to rise slowly with organics?

Hey folks, I am trying to get the PH of my soil mix right with dolomite lime. It seems my in my last grow, and in this grow, my PH rises over time. I was wondering if this was normal? I use AACT's in an organic soil, every other watering. On my current set up I mixed the hell out of my soil and the PH of a soil/distilled water slurry before I started was 6.5, now it is at 7.4-7.5 1 month into veg. Should I be mixing my soil to be 6.5 at the begining, or instead should I shoot for a lower value and expect it to rise with my AACT applications?

I am using a my varient of subcools super soil. Same recipe except my base is pro-mix. the PH of it after sitting for well over a month is 5.4, It takes 1/3 a cup of dolo lime per gallon to make it 6.5.

Bargar said:

Hey folks, I am trying to get the PH of my soil mix right with dolomite lime. It seems my in my last grow, and in this grow, my PH rises over time. I was wondering if this was normal? I use AACT's in an organic soil, every other watering. On my current set up I mixed the hell out of my soil and the PH of a soil/distilled water slurry before I started was 6.5, now it is at 7.4-7.5 1 month into veg. Should I be mixing my soil to be 6.5 at the begining, or instead should I shoot for a lower value and expect it to rise with my AACT applications?

I am using a my varient of subcools super soil. Same recipe except my base is pro-mix. the PH of it after sitting for well over a month is 5.4, It takes 1/3 a cup of dolo lime per gallon to make it 6.5.

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if i were you, i would use 1 cup of dolomite lime per cubic foot and either throw away your PH meter or put it in your closet because you wont need it. this is what i use and i dump fish fertilizer, which is like ph 4, and i also use regular tap water as is which is around 7.5 to 8 here, and i never have not 1 problem.

If my calculations are right, that would put you starting out with a PH of 6.0-6.2, which i guess makes sense if it is rising slowly throughout the grow, while you add a higher PH water to it. Have you checked the PH of your medium at the begining and end farmerjoe? I have tried to not use a meter, but its so.... useful!

I use Compost teas filled with microbes ready to wreck the organic material in my soil. My question is how does that affect PH short, and long term? Because what started out as 6.5, shot up a whole point in a months time.

Bargar said:

I am using a my varient of subcools super soil. Same recipe except my base is pro-mix. the PH of it after sitting for well over a month is 5.4, It takes 1/3 a cup of dolo lime per gallon to make it 6.5.

Click to expand...

Your pH meter is getting you in trouble since you are adding over 2x the amount of lime needed (1/3 cup/gallon), when all you need is 1cup/cf (7.5 gallons).

Lime is slow to break down and keeps breaking down over time, like months. It it's a bit low at first, no worries, it will come up. You should add the 1cup/cf, wait a month and THEN check the pH. I'll bet you added some lime, checked it too soon and added more.

BTW, most organic foods/teas are on the acidic side.

How do the plants look? If they look good, leave them alone and don't try and 'fix' anything.

Like farmerjoe (Happy 420! and +rep), my pH meter hasn't been out of the box for over 9 months and that was to brew a batch of AEM. I also add stuff with pH's in the 4's to over 10 and no problems.

Wet

Bargar said:

Hey folks, I am trying to get the PH of my soil mix right with dolomite lime. It seems my in my last grow, and in this grow, my PH rises over time. I was wondering if this was normal? I use AACT's in an organic soil, every other watering. On my current set up I mixed the hell out of my soil and the PH of a soil/distilled water slurry before I started was 6.5, now it is at 7.4-7.5 1 month into veg. Should I be mixing my soil to be 6.5 at the begining, or instead should I shoot for a lower value and expect it to rise with my AACT applications?

I am using a my varient of subcools super soil. Same recipe except my base is pro-mix. the PH of it after sitting for well over a month is 5.4, It takes 1/3 a cup of dolo lime per gallon to make it 6.5.

Click to expand...

Are the plants showing signs of stress or something else that would indicate the ph is off and needs to be adjusted?

Your pH meter is getting you in trouble since you are adding over 2x the amount of lime needed (1/3 cup/gallon), when all you need is 1cup/cf (7.5 gallons).

Lime is slow to break down and keeps breaking down over time, like months. It it's a bit low at first, no worries, it will come up. You should add the 1cup/cf, wait a month and THEN check the pH. I'll bet you added some lime, checked it too soon and added more.

BTW, most organic foods/teas are on the acidic side.

How do the plants look? If they look good, leave them alone and don't try and 'fix' anything.

Like farmerjoe (Happy 420! and +rep), my pH meter hasn't been out of the box for over 9 months and that was to brew a batch of AEM. I also add stuff with pH's in the 4's to over 10 and no problems.

Wet

Click to expand...

That explains why my PH is 7.5 now instead of in the desired range... I guess I will box up my meter and jump on the bandwagon.

Are the plants showing signs of stress or something else that would indicate the ph is off and needs to be adjusted?

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Red spots on some lower fan leaves, with a little yellowing. It's the same signs of the PH being off that my coco plants showed when the reservoiur was over 6.0.... I guess since I have moved back to soil I have to rewire my brain on how to take care of these guys.

I appreciate all of yalls help, and I apologize for posting so many questions recently, I'm just one hard headed SoB. Thanks again RIU!

Bargar said:

If my calculations are right, that would put you starting out with a PH of 6.0-6.2, which i guess makes sense if it is rising slowly throughout the grow, while you add a higher PH water to it. Have you checked the PH of your medium at the begining and end farmerjoe? I have tried to not use a meter, but its so.... useful!

I use Compost teas filled with microbes ready to wreck the organic material in my soil. My question is how does that affect PH short, and long term? Because what started out as 6.5, shot up a whole point in a months time.

Click to expand...

in the beginning i did check ph but didnt make adjustments because i wanted to see if the lime really did work. i noticed that my nutrient solutions ranged from 3.5 to 5 and my water at its highest was over 8. the best part of that experiment was that the buffering of the medium worked regardless of the PH of anything i added. since ive learned about buffering , i dont even bother checking the PH of anything. when i first tried buffering the soil and not adjusting the ph of anything, i was worried but i sat still and didnt do anything. after about 6 weeks of not adjusting the ph of anything, i realized that my plants were happier than ever, and i also saved alot of time making adjustments and also alot of money on unneeded products. if your medium contains humus and lots of microbes, which they should if you add compost to your medium and apply teas as you say, you shouldnt have any PH problems. like wet said, your meter is gonna get you in trouble. add 1 cup per cu ft, and sit back and relax and i bet you everything will go great.