pH and nutrient problems in organic soil

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
 

Sidvicious1

Active Member
I'm also doing my first living organic grow so I'm new to everything as well. List the amendments uve added besides the promix and that will give people on here a better understanding of what's going on and they can maybe help u out there with the ph problem. Honestly there is tons of great advice on this site, I would recommend just going through threads on the organic forum and I will probably find the info u need. Also, with organic u do use nutes, it just has to be labeled organic or all natural. I can just go with the mix and still grow somthing thats decent but if I u want to give it a kick in the ass Stuff like blood meal for N and bone meal for P and ive read kelp meal is great for K. so if u havnt added anything else to the mix i would for sure add ewc and perlite. also a good bit of organic matter like cow, rabbit, chicken shit. With the cal mag, I got some advice from a guy that seems to know what's up about organics and he suggested camg+ by general organics but don't use the recommended amount if ur useing ro water. Just use About 6 drops in a gal of water whenever u water. If u have a tds, ppm meter u should try and get it around 25 ppm..is the sweet spot..
 

Sidvicious1

Active Member
Also look into reading about coconut water for cal and mg. It's suposably great and adds other beneficial elements..
 

greasemonkeymann

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
whats goin on man
ok, so first things first, the #1 most common mistake people do when first doing organics is over watering. Usually caused from one of two things, the first is many are coming from a hydroponic background, and those growing medias tend to not hold onto water/nutrients the same as a mixed organic/humus based media, so in doing that they can not allow the entire soil to become dry. OR if the plant was transplanted too early into a big container.
the second is from not having the right type/mix/ of aeration in their soil.
its especially shitty if you mixed the two, meaning if not only was the soil not aerated enough but having the plant transplanted into a container INTO that soil.
so that's my hunch. An issue with aeration.

now i know what you are gonna say
"so why am i seeing what looks to be a deficiency?"

the answer is simple, a media too wet is going to be acidic, and going to have anaerobic microbes overpopulate the aerobic ones, couple that with the sheer fact of the roots being suffocated and the plant won't take up any nutrients at all. Which of course compounds the whole situation to begin with

ok, now the next part isn't really directed at your situation, but since you mentioned it i felt it was worth saying.
your comment on how organics should work (no ph'ing, no nutrients) the important thing to remember in organics is this, what you said is true, sorta, yea, you can go without ever adjusting the PH, yea you can go a couple grows without feeding BUT...

and this is big one, ALL that is predicated on the soil being assembled correctly in the first place.
and another thing worth mentioning is the RO water being used is something you'd have to compensate in that soil.
further still the media you choose makes a difference too, using RO water and a coco based soil would need some serious amendments to compensate for the imbalance of cations,
Under no circumstance can a healthy plant be grown with no nutrients, but i think what you meant was by not adding additional nutrients to the soil, like teas and such.
But obviously you do need nutrients present to grow plants. But i don't think you meant that

that all being said the maine mixes are generally pretty good, from what i hear anyways.
Also those mixes won't be shy on the calcium or magnesium with the ingredients they listed.
 

Chrisz0825

Active Member
whats goin on man
ok, so first things first, the #1 most common mistake people do when first doing organics is over watering. Usually caused from one of two things, the first is many are coming from a hydroponic background, and those growing medias tend to not hold onto water/nutrients the same as a mixed organic/humus based media, so in doing that they can not allow the entire soil to become dry. OR if the plant was transplanted too early into a big container.
the second is from not having the right type/mix/ of aeration in their soil.
its especially shitty if you mixed the two, meaning if not only was the soil not aerated enough but having the plant transplanted into a container INTO that soil.
so that's my hunch. An issue with aeration.

now i know what you are gonna say
"so why am i seeing what looks to be a deficiency?"

the answer is simple, a media too wet is going to be acidic, and going to have anaerobic microbes overpopulate the aerobic ones, couple that with the sheer fact of the roots being suffocated and the plant won't take up any nutrients at all. Which of course compounds the whole situation to begin with

ok, now the next part isn't really directed at your situation, but since you mentioned it i felt it was worth saying.
your comment on how organics should work (no ph'ing, no nutrients) the important thing to remember in organics is this, what you said is true, sorta, yea, you can go without ever adjusting the PH, yea you can go a couple grows without feeding BUT...

and this is big one, ALL that is predicated on the soil being assembled correctly in the first place.
and another thing worth mentioning is the RO water being used is something you'd have to compensate in that soil.
further still the media you choose makes a difference too, using RO water and a coco based soil would need some serious amendments to compensate for the imbalance of cations,
Under no circumstance can a healthy plant be grown with no nutrients, but i think what you meant was by not adding additional nutrients to the soil, like teas and such.
But obviously you do need nutrients present to grow plants. But i don't think you meant that

that all being said the maine mixes are generally pretty good, from what i hear anyways.
Also those mixes won't be shy on the calcium or magnesium with the ingredients they listed.
I'm pretty good about not overwatering. Not saying it's perfect. Especially switching to a new soil. I've always used ffof which is a lot lighter than coast of maine. I'm still adjusting to the weight difference when I lift my pots to see if they need water. Also I stick my finger first knuckle deep into the soil and if it's dry, and the pot feels light enough, I water. So maybe when I think it's time to water, I'll wait a day then water.
 

greasemonkeymann

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
is there something wrong with your tap water?
i prefer tap or well water to RO water, personally.
also growing comfrey will get you all the cal and mag that you need... and at a great ratio
and nitrogen, and potassium, as well as many other micronutrients, all chelated by nature, and ready to be absorbed by the plant at a nitrogen to carbon ration that has it melt away in days.
good shit, and using that and you're guaranteed you'll never have a cal mag def again
 

greasemonkeymann

Well-Known Member
I'm pretty good about not overwatering. Not saying it's perfect. Especially switching to a new soil. I've always used ffof which is a lot lighter than coast of maine. I'm still adjusting to the weight difference when I lift my pots to see if they need water. Also I stick my finger first knuckle deep into the soil and if it's dry, and the pot feels light enough, I water. So maybe when I think it's time to water, I'll wait a day then water.
that's a good method to determine if they are thirsty, if you are doing that each time i doubt it's overwatering.
hmmm... did you add anything heavy in potassium?
what size containers are they in?
 

Chrisz0825

Active Member
that's a good method to determine if they are thirsty, if you are doing that each time i doubt it's overwatering.
hmmm... did you add anything heavy in potassium?
what size containers are they in?
I haven't added anything. Just straight coast of maine soil. They are in 5 gallon smart pots
 

Chrisz0825

Active Member
is there something wrong with your tap water?
i prefer tap or well water to RO water, personally.
also growing comfrey will get you all the cal and mag that you need... and at a great ratio
and nitrogen, and potassium, as well as many other micronutrients, all chelated by nature, and ready to be absorbed by the plant at a nitrogen to carbon ration that has it melt away in days.
good shit, and using that and you're guaranteed you'll never have a cal mag def again
Not sure of the pH of my tap water. But I will test it.
is there something wrong with your tap water?
i prefer tap or well water to RO water, personally.
also growing comfrey will get you all the cal and mag that you need... and at a great ratio
and nitrogen, and potassium, as well as many other micronutrients, all chelated by nature, and ready to be absorbed by the plant at a nitrogen to carbon ration that has it melt away in days.
good shit, and using that and you're guaranteed you'll never have a cal mag def again
I just measured the pH in both tap and ro and they are both about the same. Tap is 8.8 and ro is 8.2 Ppm is 211 in tap and 10 in ro
 
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Chrisz0825

Active Member
that's a good method to determine if they are thirsty, if you are doing that each time i doubt it's overwatering.
hmmm... did you add anything heavy in potassium?
what size containers are they in?
What if I add pulverized dolomite lime the next time I water to give it some cal/mag? Or what about a compost tea like bonticare pure blend?
 

tpc_mikey

Well-Known Member
I typically amend my organic soil with some hi cal dolomite lime but even doing that as its very slow realease i still have to add some epsom salt to my waterings, try that if your having a cal mag issue but truthfully i use straight tap water have never tested the ph of it and my grows turn out just fine, sometimes we over think things and thats the purpose of organics in the growing process at least for me, give the plant a healthy home and all you have to do is dump some water on it every 3 or 4 days :)
 

greasemonkeymann

Well-Known Member
I typically amend my organic soil with some hi cal dolomite lime but even doing that as its very slow realease i still have to add some epsom salt to my waterings, try that if your having a cal mag issue but truthfully i use straight tap water have never tested the ph of it and my grows turn out just fine, in the growing process at least for me, give the plant a healthy home and all you have to do is dump some water sometimes we over think things and thats the purpose of organics on it every 3 or 4 days :)
good advice man
What if I add pulverized dolomite lime the next time I water to give it some cal/mag? Or what about a compost tea like bonticare pure blend?
the concern i'd have is why is the 5 gallon container devoid of calcium?
i don't think it's that, to be honest.
considering the plant is only 5 weeks old i can almost guarantee that it's not a deficiency at all.
5 weeks old, and 5 gallons of soil, those two things can pretty much rule out a def.
you follow me?

when did you transplant?
i reaaaally urge people to NOT trans into a large container at that early of age, and i also recommend transplanting multiple times before it gets to it's "final" container.
reason being is that it can retain too much water, and furthermore, if you are in fact picking up the pot each time to see if it needs water, then what is happening (and you may not even realize this) but moving around smartpots will make them settle.... and then you end up with aeration at the top, and aeration on the sides, and the bottom and middle are dense humus and that turns anaerobic.
one of the reasons i don't like fabric pots...

honestlt man, i still stand by my earlier hunch

i really think they are getting too much water, that coupled with the container being too big and the media likely retaining too much water.
i'm not saying you are watering when they are still wet, i'm saying that you are watering when the middle of the container is still damp, and with the fairly small root system of a 5 wk old plant, that won't uptake very much water either.
but the problem sorta perpetuates itself, because as you water soil with no roots to keep it's structure you end up "floating" up the lighter materials (aeration, wood chips, etc) while "settleing" the more fine particulates, humus, peat, compost, etc. so what happens is the entire soil structure gets plugged from the settling.
sorta like goldpanning

My point is this, if you try to correct a calmag deficiency you are going to exacerbate or at the least prolong the issue.
at least that's my hunch on this anyways.
but i'd bet a small amount of money on it
 
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Chrisz0825

Active Member
good advice man

the concern i'd have is why is the 5 gallon container devoid of calcium?
i don't think it's that, to be honest.
considering the plant is only 5 weeks old i can almost guarantee that it's not a deficiency at all.
5 weeks old, and 5 gallons of soil, those two things can pretty much rule out a def.
you follow me?

when did you transplant?
i reaaaally urge people to NOT trans into a large container at that early of age, and i also recommend transplanting multiple times before it gets to it's "final" container.
reason being is that it can retain too much water, and furthermore, if you are in fact picking up the pot each time to see if it needs water, then what is happening (and you may not even realize this) but moving around smartpots will make them settle.... and then you end up with aeration at the top, and aeration on the sides, and the bottom and middle are dense humus and that turns anaerobic.
one of the reasons i don't like fabric pots...

honestlt man, i still stand by my earlier hunch

i really think they are getting too much water, that coupled with the container being too big and the media likely retaining too much water.
i'm not saying you are watering when they are still wet, i'm saying that you are watering when the middle of the container is still damp, and with the fairly small root system of a 5 wk old plant, that won't uptake very much water either.
but the problem sorta perpetuates itself, because as you water soil with no roots to keep it's structure you end up "floating" up the lighter materials (aeration, wood chips, etc) while "settleing" the more fine particulates, humus, peat, compost, etc. so what happens is the entire soil structure gets plugged from the settling.
sorta like goldpanning

My point is this, if you try to correct a calmag deficiency you are going to exacerbate or at the least prolong the issue.
at least that's my hunch on this anyways.
but i'd bet a small amount of money on it
I actually do not transplant. 4 outta 5 of my grows have been taking a germinated seed and placing it straight into final pot. The one time I did transplant she went into shock. So I just try to avoid transplanting all together. I happen to come across an article about coast of maine soil and it explained, 1.5 cubic feet of soil is enough to feed a single plant its entire life in a 15 gallon bucket. I divided it up into 2 5 gallon bucks. So less soil, less nutrients, add organic nutrients. So I ordered a 4 lb bag of coast of maine organic plant food and gonna top dress my soil with that. Fingers crossed. But I will definitely be more cautious about my watering. Just wait till pot is light and wait an extra day
 

OldMedUser

Well-Known Member
I'd wait until you think it needs watering then wait until the plant actually starts to droop before watering just the once so you can feel the weight of a truly dry pot and get a better feel for how long to wait before soaking it good again.

Like @greasemonkeymann was saying, there's no way that a 5 week old plant could deplete 5gal of good soil of it's nutes yet and it's best to do a few transplants until you get to the final pot. I hack off long roots at each transplant and never see any shock so I'm not sure what you are doing wrong to be so adverse to repotting. I just let the plants get almost dry then pop them out and drop them in the bigger pot already filled at the bottom to get the height right then fill in the sides, lightly tamping the new soil in as I go, then soak the whole thing down real good and let it sit in it's runoff for an hour or so to make sure there are no dry pockets of soil in the pot then remove the runoff.

I'd bet that 75% of your roots are in the bottom 25% of your pots but with those fabric bags you can't easily pop the plant out of it's container to check on the roots like with plastic pots. That's why I cut off the bottom of the rootball at each transplant is to make them branch out and produce a lot more fine feeder roots that fill the pot from top to bottom.

Any long roots are shaved off the sides as well so they all branch out too.

RootPrune02.jpg
 

OldMedUser

Well-Known Member
Not sure of the pH of my tap water. But I will test it.

I just measured the pH in both tap and ro and they are both about the same. Tap is 8.8 and ro is 8.2 Ppm is 211 in tap and 10 in ro
RO water has no real pH of it's own and is like a blank slate waiting for things to be added to it to give it a pH. Add any nutes you are going to use to it first before checking pH and don't leave the pH pen sitting in RO water as it will leach the salts out of the glass ball and destroy the probe.

And RO water doesn't "steal" the Ca and Mg out of the water. It just has none of it's own to add to the mix. We drink RO water here and I add some Coral Calcium powder and some pink Himalayan sea salt to it to add some minerals that raise it's pH and adds some healthy minerals while improving the taste. The coral calcium would be good for plants but is pretty pricey. Fairly sure it's organic as well.

:peace:
 

dubekoms

Well-Known Member
Coast of Maine is good shit. They use a lot of lobster shells in their compost for calcium so I don't see any problems there. Have you tried their new Stonington blend? I'm pretty sure they developed it specifically for weed. Usually if im having issues in new soil I just make a simple ewc tea and it sets everything right.1\3 cup mollases, 2 cups worm castings in 5 gal water bubbled for 36 hours. Let the pot dry out a bit and water.
 

greasemonkeymann

Well-Known Member
I actually do not transplant. 4 outta 5 of my grows have been taking a germinated seed and placing it straight into final pot. The one time I did transplant she went into shock. So I just try to avoid transplanting all together. I happen to come across an article about coast of maine soil and it explained, 1.5 cubic feet of soil is enough to feed a single plant its entire life in a 15 gallon bucket. I divided it up into 2 5 gallon bucks. So less soil, less nutrients, add organic nutrients. So I ordered a 4 lb bag of coast of maine organic plant food and gonna top dress my soil with that. Fingers crossed. But I will definitely be more cautious about my watering. Just wait till pot is light and wait an extra day
hmmm, well that's very different than what i'd do, but doesn't mean you are wrong.
my concern is that added uncycled nutrients as a topdress is only going to exacerbate the condition, but that's all based on incomplete information and conjecture so it's hard to say for sure, buuuut....... i just hope it turns out alright for ya
but yea, i'd say a 1.5 cubic foot of amended soil can grow a plant water only for a single season. Sure
but only inside, if you did that outside you'd run into nitrogen defs fairly fast
at least in sunny CA you would
but all that is massively predicated on the soil structure, you can have all the nutrients in the world but if the soil isn't "breathing" well enough it will have all sorts of problems.
 

Chrisz0825

Active Member
hmmm, well that's very different than what i'd do, but doesn't mean you are wrong.
my concern is that added uncycled nutrients as a topdress is only going to exacerbate the condition, but that's all based on incomplete information and conjecture so it's hard to say for sure, buuuut....... i just hope it turns out alright for ya
but yea, i'd say a 1.5 cubic foot of amended soil can grow a plant water only for a single season. Sure
but only inside, if you did that outside you'd run into nitrogen defs fairly fast
at least in sunny CA you would
but all that is massively predicated on the soil structure, you can have all the nutrients in the world but if the soil isn't "breathing" well enough it will have all sorts of problems.
I bought a soil pH reading that also has a moisture reader. My soil is about 6.8 but I noticed that even though my pot feels empty and I would normally water, in the center of the pot it's still pretty damn moist. So I think it conclusion, I was just overwatering. I have some organic plant food I got from coast of maine...in this video I watched the lady said over time you may have to add a bit. So if by correcting my overwatering problem doesn't fix this then I'll top dress.
 

tpc_mikey

Well-Known Member
And yes if your growing organically you will have to do some top dressings during the life cycle, I use pure worm castings and some small amounts of bat guano for my N during the end of veg and first few weeks of flower during the stretch, then i top dress with some kelp meal during 2nd week of flower also. My soil is amended with kelp meal and tomato tone from the beginning, this grow i will be suplimenting with small amounts of tiger bloom for some added P and K, Here is a few updated photos of her tonite, she is in 15th day of 12/12, this plant is having a slight cal mag issue can see it in the leaf tacoing and drawstringing, but think i got it under control now. Dolomite lime is very slow release.IMG_1930.JPG IMG_1932.JPG IMG_1933.JPG
IMG_1929.JPG
 

greasemonkeymann

Well-Known Member
I bought a soil pH reading that also has a moisture reader. My soil is about 6.8 but I noticed that even though my pot feels empty and I would normally water, in the center of the pot it's still pretty damn moist. So I think it conclusion, I was just overwatering. I have some organic plant food I got from coast of maine...in this video I watched the lady said over time you may have to add a bit. So if by correcting my overwatering problem doesn't fix this then I'll top dress.
EXACTLY
that was my hunch, only reason I kinda knew that is because it's happened to me many times, I really really do not like fabric pots for any grows except outdoor and somewhat high temps, otherwise they simply do not hold the soil ideally, and it really is crucial that the soil is assembled/mixed right when transplanted, with attention especially delivered to watering techniques. It can sound almost asinine but there really is a particular way that you should water plants, and I've seen a whoooole lot of growers skip or simply disregard the way you should water a plant in an organic soil.
often times the simplest things get overlooked and people end up barking at the wrong tree and waaaay overanalyzing the problem.
too damn often the problem is simply a damp soil, and cannabis just will not do well with wet-feet.
whats confusing to many many growers is that a poorly aerated soil will replicate, exactly, many different defs all at once, and its super common for them to try and remedy it by feeding it, which almost always makes the problem worse.
in fact, if anytime you suspect that a new mix isn't aerated enough, what works almost 100% to fix it, is .to "dilute" the questionable mix with equal portions of promix.
 
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