Here's a good read about nutrient balance

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MIMedGrower

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Good article. And more information showing cannabis never needs extra phosphorous. Not even as a bloom signal. It just doesn't utilize it.


Advanced nutrients and dyna grow ran tests that prove the same but they still sell the bloom bottles. Lol.


They hope no one actually reads their own tests? ;-)
 
HeathenFarmer

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Interesting. So in a nutrient rich soil grow, any further application of P after a certain point (for instance after stretch) would basically be unnecessary? Am I understanding that correctly? However K, cal,mag, and micros would still be needed?
 
boomgagem

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Interesting. So in a nutrient rich soil grow, any further application of P after a certain point (for instance after stretch) would basically be unnecessary? Am I understanding that correctly? However K, cal,mag, and micros would still be needed?

Thats what I took from it. I just wonder how using RO vs tap water affects those ratios, if you don’t know what’s in your water of course.

my tap water ppm is only 76, and it leaves a white residue on bathroom fixtures after a few showers, so I assume it’s mostly calcium and sodium. I just want to adjust feeding with the tap ppm in mind.

ive got an RO system installed but I’ve been advised to not use it and just use the tap
 
HeathenFarmer

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I'm sure there's a known baseline cal/mag dosage for RO water, but with tap we're shooting in the dark. I water my plants with tap water after it's run through a brita filter and left out overnight. That changes the ph down slightly but I'm not sure about calcium. I would think activated carbon would filter some of the calcium but not completely strip it like RO? I think that's what's lowering my water ph when I filter it.
In either case I've been adding a very light amount of calmag to my water, like an 1/8th of recommended dose, and watching carefully for excess/def. From the article it sounds like it's used all the way through flowering.
 
Aqua Man

Aqua Man

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Imo P a week before flip a P boost helps if indoors.... they generally don't get as much veg time or the sudden change in light duration which from my understanding causes a bit high demand for P at flip so getting a it a boost a week early I feel will benefit.

Also feel (no proof) P after stretch is useless and K, Ca and Mg rario are extremely important the entire grow. As these are the ones that usually (along with P) are responsible for nutrient imbalances that cause deficiencies.
 
HeathenFarmer

HeathenFarmer

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By sheer dumb luck I gave the plants their first shot of 0-16-16 about five days ago, and flipped today. I need to look into some 0-0-16 or something along those lines as I'm sure the FFOF I'm using already has some P available in it, at least probably enough to finish.
 
Aqua Man

Aqua Man

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I'm sure there's a known baseline cal/mag dosage for RO water, but with tap we're shooting in the dark. I water my plants with tap water after it's run through a brita filter and left out overnight. That changes the ph down slightly but I'm not sure about calcium. I would think activated carbon would filter some of the calcium but not completely strip it like RO? I think that's what's lowering my water ph when I filter it.
In either case I've been adding a very light amount of calmag to my water, like an 1/8th of recommended dose, and watching carefully for excess/def. From the article it sounds like it's used all the way through flowering.
Honestly like stated and I do the same... K 200ppm, CA 100ppm, Mg 50ppm. This is why I use only mag sulfate in addition to my tap water because it much higher as most are in CA than Mg. So between my nutes and tap I have enough CA and lack Mg.

100-120ppm nitrate, P I keep around 30ppm

Ratios..... its all about the ratios.... N to K 1 to 1.5/2, K to Ca 2 to 1, CA to Mg 2 to 1, Mg to P 2 to 1.

Adjust the ppm and should not have an issue. Most problems start when ppl start throwing in all the bottles of unicorn piss that all have the same shit and throwing their ratios all out.
 
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HeathenFarmer

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I've only ever grown in soil, but I'm tempted to try DWC next. There's no way for me to know what my ratios are, as I don't know what's available in the soil, only what I'm adding. Or am I overthinking it? I do have an EC/ppm meter but haven't used it yet to measure ppm. Just been adding weak nutes once a week and ph'ing.
 
boomgagem

boomgagem

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Honestly like stated and I do the same... K 200ppm, CA 100ppm, Mg 50ppm. This is why I use only mag sulfate in addition to my tap water because it much higher as most are in CA than Mg. So between my nutes and tap I have enough CA and lack Mg.

100-120ppm nitrate, P I keep around 30ppm

Ratios..... its all about the ratios.... N to K 1 to 1.5/2, K to Ca 2 to 1, CA to Mg 2 to 2, Mg to P 2 to 1.

Adjust the ppm and should not have an issue. Most problems start when ppl start throwing in all the bottles of unicorn piss that all have the same shit and throwing their ratios all out.

Exactly! And I don’t want to make that mistake. I should have just stayed with coco instead of trying this coco loco. And fox farms 28 bottles of shit lol
 
Aqua Man

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I'm not an organic guy or soil... but most preferted stuff should fall within similar ratios. I'm to much of a control freak so coco and hydro with synthetics works for me.... many very good organic growers here that probably have ideal mixes to achieve the same
 
boomgagem

boomgagem

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I'm not an organic guy or soil... but most preferted stuff should fall within similar ratios. I'm to much of a control freak so coco and hydro with synthetics works for me.... many very good organic growers here that probably have ideal mixes to achieve the same

Definitely going back to coco after this current grow.
 
MIMedGrower

MIMedGrower

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Imo P a week before flip a P boost helps if indoors.... they generally don't get as much veg time or the sudden change in light duration which from my understanding causes a bit high demand for P at flip so getting a it a boost a week early I feel will benefit.

Also feel (no proof) P after stretch is useless and K, Ca and Mg rario are extremely important the entire grow. As these are the ones that usually (along with P) are responsible for nutrient imbalances that cause deficiencies.


the president of dyna grow emailed back that the extra P is only used as a signal indoors to help the plant initiate flowering. And it is not needed out doors.


im not sure i even agree with that logic. Why would a boost of a mineral the plant does not use much of help with flowering. K is more for branching.

That article said they are still testing the P before transition.
 
Aqua Man

Aqua Man

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the president of dyna grow emailed back that the extra P is only used as a signal indoors to help the plant initiate flowering. And it is not needed out doors.


im not sure i even agree with that logic. Why would a boost of a mineral the plant does not use much of help with flowering. K is more for branching.

That article said they are still testing the P before transition.
Yeah I have no proof... but feel I did notice a slight increase to bud onset (new strain so can't verify) and reduced purpling in the stocks (again no proof just observation) I have only done this 2 grows I think now so it's only my opinion and I have no studies or personal tests to back that up... but I do feel confident enough to continue and have a cautious opinion.

Bit I also typically run very short veg times so less time to accumulate
 
MIMedGrower

MIMedGrower

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Yeah I have no proof... but feel I did notice a slight increase to bud onset (new strain so can't verify) and reduced purpling in the stocks (again no proof just observation) I have only done this 2 grows I think now so it's only my opinion and I have no studies or personal tests to back that up... but I do feel confident enough to continue and have a cautious opinion.

Bit I also typically run very short veg times so less time to accumulate


The short veg times like you said go with that article about the frontloading of P. Well except there is not enough time to accumulate enough P for flowering.

So many variables to consider
 
Aqua Man

Aqua Man

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The short veg times like you said go with that article about the frontloading of P. Well except there is not enough time to accumulate enough P for flowering.

So many variables to consider
Yeah thays exactly what and why that popped into my mind after your comment... and that could absolutely be why I am seeing a difference. As usual always making me think 👍👍👍
 
Dirtbag

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It was @Dirtbag that shared this info with me so let's just blame him for this discussion lol... but I have to say I think personally it's really helped me. Again I cannot validate it other than my opinion at this point.

Lol that's the info that trickled down to me, but I also noticed a faster budset and healthier looking plants in stretch by frontloading P a few days to a week before transition.
But im kinda over saying this or that works or it doesn't... it's just not worth the endless debates that it often causes on here. I'm just doing what I do these days.
 

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