Organic soil ph issues

Chrisz0825

Active Member
This is my first organic grow and the soil I went with is coast of maine pro mix. From what I read, with organic soils there is no need for nutes or adjust ph. I'm also using ro water which as we all know, strips calcium and magnesium from the water. I have two girls, one pineapple express and one blue dream about 5 wks old. They were doing great up until about a wk ago or so. Now they seems to be having some ph problems as well as what I think calmag would resolve. So I'm thinking maybe I should go ahead and adjust my ph from now on and add some calmag. But would I go ahead and adjust to 6.5 or since I'm using organic soil should I offset it a little? Same with calmag. Should I use less? Why am I having these issues? With water only organic soil, I don't feel I should have to add anything but water. I'm really trying to steer clear of chemicals because I want a totally organic harvest. Is there any organic ways around adjusting ph and adding calcium and magnesium? Should I just use tap water? I'm lost here
 

Buba Blend

Well-Known Member
This is my first organic grow and the soil I went with is coast of maine pro mix. From what I read, with organic soils there is no need for nutes or adjust ph. I'm also using ro water which as we all know, strips calcium and magnesium from the water. I have two girls, one pineapple express and one blue dream about 5 wks old. They were doing great up until about a wk ago or so. Now they seems to be having some ph problems as well as what I think calmag would resolve. So I'm thinking maybe I should go ahead and adjust my ph from now on and add some calmag. But would I go ahead and adjust to 6.5 or since I'm using organic soil should I offset it a little? Same with calmag. Should I use less? Why am I having these issues? With water only organic soil, I don't feel I should have to add anything but water. I'm really trying to steer clear of chemicals because I want a totally organic harvest. Is there any organic ways around adjusting ph and adding calcium and magnesium? Should I just use tap water? I'm lost here
I can only help a little here. Do more reading on different organic soils. Some have enough nutrients to take a grow to the end with water only. Some have a very small amount of nutrients in them and need to be fed.
Might want to post your organic questions here:

https://www.rollitup.org/f/organics.59/
 

Rasta Roy

Well-Known Member
Most organic bagged soils are gonna fart out on you about five weeks into flower! Some oyster shell flour, neem seed meal, gypsum, fish bone meal, and Langbeinite mixed into your soil would keep it ripe and keep you sticking with just water.
 

Borgarden

Well-Known Member
If it is actually a true organic soil you don't need to ph your water at all the bacteria in the soil does all the work however they need food just like a normal potting mix does. Most organics guys give the soils "teas" to give them a boost and keep the bacteria happy and healthy. Look them up they might help you out. The only time you will have ph problems with organic soil is if you killed the bacteria/microbes in the soil by using ferts on them instead of organic stuff like the guy above me suggested which is apparently a big no no.
 

RayRay747

Well-Known Member
@Borgarden: What if your pH after adding your liquids (molasses, aloe vera juice and coconut juice for example) is at 4.8-5.0? Would you still feed that water to your plants considering the pH level?

Or should you use baking soda to bring the pH up to 6.5 range?

I am stumped here as this is an issue I am having as I feel the water should be pH'd but I have read people say dont adjust the pH when feeding "true" organic soil. I am using Stonington Blend "Super Soil" and I was told by Coast of Maine that I would just need to add water and around the start of flowering to give it some of their Stonington Organic Plant food.
 
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Always PH your water what is your water is very acidic or alcaline? might as well just ph it, whenever i add organic nutes to my water mix the ph drops ALOT
 

RayRay747

Well-Known Member
Always PH your water what is your water is very acidic or alcaline? might as well just ph it, whenever i add organic nutes to my water mix the ph drops ALOT
It comes out the tap around 7.5-7.7. I slow boil the water with a half cut-up orange to remove the chlorine and chloramine and let it sit open with a bug mesh over top for 24-48 hours. When I retest the pH its around 7.4-7.5. When I add the molasses, aloe vera juice and coconut water, it drops to 4.8-5.0. I did read somewhere tho that aloe vera juice will lower your pH. Which I suspect is the reason it drops so much.

Now thinking back, I may have put in too much aloe vera. I doubled what I normally would put in and that is what might have caused the drop in pH.

However, I have read numerous times saying do not adjust your pH when using super soil. I just dont see how I can feed my plants water that is around the 4.8-5.0 range. Doesnt seem right to me even with amended soil.
 

Nutty sKunK

Well-Known Member
It comes out the tap around 7.5-7.7. I slow boil the water with a half cut-up orange to remove the chlorine and chloramine and let it sit open with a bug mesh over top for 24-48 hours. When I retest the pH its around 7.4-7.5. When I add the molasses, aloe vera juice and coconut water, it drops to 4.8-5.0. I did read somewhere tho that aloe vera juice will lower your pH. Which I suspect is the reason it drops so much.

Now thinking back, I may have put in too much aloe vera. I doubled what I normally would put in and that is what might have caused the drop in pH.

However, I have read numerous times saying do not adjust your pH when using super soil. I just dont see how I can feed my plants water that is around the 4.8-5.0 range. Doesnt seem right to me even with amended soil.

Your soil will buffer it though. Yes it’s acidic but nothing to worry about as around the rhizophere (root zone) there’s a special relationship going on. Without that plants can’t absorb the nutrients in the soil.

I just feed them whatever the PH is. Think it’s been around the 5.6 mark recently and I’m growing in soil. Also water only days are ph 8. Although my soil has been limed for the buffering qualities.
 

Lordhooha

Well-Known Member
It comes out the tap around 7.5-7.7. I slow boil the water with a half cut-up orange to remove the chlorine and chloramine and let it sit open with a bug mesh over top for 24-48 hours. When I retest the pH its around 7.4-7.5. When I add the molasses, aloe vera juice and coconut water, it drops to 4.8-5.0. I did read somewhere tho that aloe vera juice will lower your pH. Which I suspect is the reason it drops so much.

Now thinking back, I may have put in too much aloe vera. I doubled what I normally would put in and that is what might have caused the drop in pH.

However, I have read numerous times saying do not adjust your pH when using super soil. I just dont see how I can feed my plants water that is around the 4.8-5.0 range. Doesnt seem right to me even with amended soil.
I’m with the rest any good soil will buffer the ph just fine when growing in soil I simply pour my water and nutrients in. I only ph my rdwc room. If the soil is built up correctly it will do fine as long as it not battery acid level.
 

Rasta Roy

Well-Known Member
I slow boil the water with a half cut-up orange to remove the chlorine and chloramine and let it sit open with a bug mesh over top for 24-48 hours.

I just dont see how I can feed my plants water that is around the 4.8-5.0 range. Doesnt seem right to me even with amended soil.
Stop wasting your oranges friend, just letting your water sit will produce the same results.

You just think that because hydrogrowers think they know what they're doing and have been good about spreading bad information. Lol.

My tap water comes out above 8 on the ph scale consistently. It sits in a res with an air pump until I need it. I don't touch it.
 

MichiganMedGrower

Well-Known Member
I use 8.0 well water in ocean forest without ever adjusting ph every Grow for years.

But my water is relatively soft. It tests at .2 ec or 100ppm.

The oyster shell in the mix buffers the soil back to about 6.5 ph every time I check. Lime is the buffer in other soils.

You only need to ph down water if it is very high in minerals. Hard alkaline water can make the ph rise over time as you keep pouring minerals in that are in the hard water. The ph has nothing to do with it. It doesn’t always match the hardness.

The thing that is important is water alkalinity. And that determines how it will react with your nutes and medium.

There is no standard answer here. Ph’ing for no reason will acidify your soil over time.

And ro water is not good for soil. No alkalinity. So it goes real acidic when nutes are added.

Professionals mix hard tap water with ro down to about 150ppm or .3 ec for best results. This keeps the natural minerals in the water but at the perfect alkalinity for plants.
 

Buba Blend

Well-Known Member
If you make two identical soil mixes with one difference.
One has oyster shell flower and the other has lime.
Will the soil PH be similar?
My feeling is that the lime will have a higher soil ph. IDK. Just going by the ph of my ffof soil vs my mix with lime.
 

MichiganMedGrower

Well-Known Member
If you make two identical soil mixes with one difference.
One has oyster shell flower and the other has lime.
Will the soil PH be similar?
My feeling is that the lime will have a higher soil ph. IDK. Just going by the ph of my ffof soil vs my mix with lime.
Of course. The lime or oyster shell is put in on the proper amount for the medium ph to stay stable.

Pro mix warns to test before using as sometimes clumps can form in storage and soil can be over limed.

Unless I have problems I only check ph once when I mix my soil and perlite. It has been 6.5 ph every time I checked a bag of ocean forest for years.

And pro mix Hp (they recomend testing after mix has been watered for a week) has always been 6.3 when I used it.

It is recommended to start Grows with tap water to help keep the ph up the first week while the lime charges.

Even if your water is very alkaline and you intend to filter it.
 

Buba Blend

Well-Known Member
Of course. The lime or oyster shell is put in on the proper amount for the medium ph to stay stable.

Pro mix warns to test before using as sometimes clumps can form in storage and soil can be over limed.

Unless I have problems I only check ph once when I mix my soil and perlite. It has been 6.5 ph every time I checked a bag of ocean forest for years.

And pro mix Hp (they recomend testing after mix has been watered for a week) has always been 6.3 when I used it.

It is recommended to start Grows with tap water to help keep the ph up the first week while the lime charges.

Even if your water is very alkaline and you intend to filter it.
I have been doing ro for the last 5 grows. Next grow some plants are going to get fed my old way which was tap and ro mixed to make 150 - 200 ppm water.
 

Buba Blend

Well-Known Member
Are you having alkalinity related problems?

No. Or at least I don't think so, my plants like the ph of my soil I think. I did many slurry tests at different stages with new and used ffof and it always came up as the sample on the left.
When I make a soil using used ffof and add 1 1/2 cups of garden lime to 25-30 gallons of soil the slurry test comes up like the sample on the right. Someone can test this with a small sample of ffof and espoma garden lime and post results of a before and after, takes 2+ weeks to get results. Soil should be kept slightly moist and changes will be seen in two+ weeks. If you or anyone has ffof and add a proportional amount to what I did above of espoma garden lime I'd be curious of the results.
IDK if my results are accurate in any way. Just how it appears to me at the moment.

Separately
Interesting thought. Something I need to think about.
I started using ro only 5 grows ago. I have had calcium problems for 5 grows. I chalked up the calcium problems to lock out from over watering. Hmmm!

Time for some music and to get stoned. :bongsmilie:

IMG_2176 - Copy.JPG
 

MichiganMedGrower

Well-Known Member
No. Or at least I don't think so, my plants like the ph of my soil I think. I did many slurry tests at different stages with new and used ffof and it always came up as the sample on the left.
When I make a soil using used ffof and add 1 1/2 cups of garden lime to 25-30 gallons of soil the slurry test comes up like the sample on the right. Someone can test this with a small sample of ffof and espoma garden lime and post results of a before and after, takes 2+ weeks to get results. Soil should be kept slightly moist and changes will be seen in two+ weeks. If you or anyone has ffof and add a proportional amount to what I did above of espoma garden lime I'd be curious of the results.
IDK if my results are accurate in any way. Just how it appears to me at the moment.

Separately
Interesting thought. Something I need to think about.
I started using ro only 5 grows ago. I have had calcium problems for 5 grows. I chalked up the calcium problems to lock out from over watering. Hmmm!

Time for some music and to get stoned. :bongsmilie:

View attachment 4057066

I have been having calcium deficiencies lately too and I thought it was because my well water had gone down in mineral content from .3 to .2 with the dry summer we had.

Turns out it was an old bag of ocean forest that I mixed too much perlite into. Maybe more than 25% large perlite.

I added 1/4 cup lime to it to try to fix the problem and it helped green up the next plants but the deficiency came back anyway.

After 3 months the organic nutrients in soil mix can be eaten by the bacteria and be out of balance.

Fox farm recommends 6 months old at most. Pro mix 1 year from bag date. The chemical salt nute charge, lime and wetting agent will deteriorate.

I over compensated with cal mag too. Got nitrogen tox on top of cal problems.

New bag and the problems went away.

When I test a new bag or an overbites pot I get the acidic reading you show.

If I test in a week or a healthy plant I get the color on the right. About 6.5.

When plants eat the ph rises. When lime is activated by water the ph rises. Most nutes bring it down. It should all balance out.
 

Buba Blend

Well-Known Member
I have been having calcium deficiencies lately too and I thought it was because my well water had gone down in mineral content from .3 to .2 with the dry summer we had.

Turns out it was an old bag of ocean forest that I mixed too much perlite into. Maybe more than 25% large perlite.

I added 1/4 cup lime to it to try to fix the problem and it helped green up the next plants but the deficiency came back anyway.

After 3 months the organic nutrients in soil mix can be eaten by the bacteria and be out of balance.

Fox farm recommends 6 months old at most. Pro mix 1 year from bag date. The chemical salt nute charge, lime and wetting agent will deteriorate.

I over compensated with cal mag too. Got nitrogen tox on top of cal problems.

New bag and the problems went away.

When I test a new bag or an overbites pot I get the acidic reading you show.

If I test in a week or a healthy plant I get the color on the right. About 6.5.

When plants eat the ph rises. When lime is activated by water the ph rises. Most nutes bring it down. It should all balance out.
Quick question.
When you over compensated with cal mag. How much were you using per gallon?
I'm up to 1 1/2 tsp per gallon cal mag+ at 4 weeks flowering near the end of stretch. I'm not sure what my plans are for the following weeks yet. I just put some tap in a 5 gallon bucket. Going to start feeding some with part tap.
 
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