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Question regarding Ca uptake in early flower and VPD

Piff_cat

Well-known member
when you first come across a problem in your plants it is never due to a lack of a nutrient your supplying. its always a question of lockout or cascade. low humidity and low temperature(especially in the rootzone) will kill your plant quickly by causing a potassium deficiency. high sodium in the rootzone locks everything out. it would take weeks for a nutrient issue to take hold if underfeeding is the issue. the problems come when something is completely denied to the plant. low humidity, light too close or too far, over watering, low leaf surface temp, low water temp, ph and ec in rootzone. 95 percent of time its one of these
 

ButterflyEffect

Well-known member
when you first come across a problem in your plants it is never due to a lack of a nutrient your supplying. its always a question of lockout or cascade. low humidity and low temperature(especially in the rootzone) will kill your plant quickly by causing a potassium deficiency. high sodium in the rootzone locks everything out. it would take weeks for a nutrient issue to take hold if underfeeding is the issue. the problems come when something is completely denied to the plant. low humidity, light too close or too far, over watering, low leaf surface temp, low water temp, ph and ec in rootzone. 95 percent of time its one of these
Agreed. Now that I'm getting a handle on the causes, I'll be deploying a controller in my veg room to make sure the environment is dialed in. It's the only room of the four that isn't controlled.
 

Broggemann

Active member
You are using this bro science you speak of. The ' I do it like this ' approach to countering what I'm putting forward from industry averages and university studies.

First, there is actually a study that found out that more than 240ppm can be detrimental for some strains.

But it's not the study you linked, because as aforementioned, you cant compare hemp (!) grown in soil (!) under the sun (!) with what we are doing here.
And even in the study I'm talking about, they only changed K levels - if they changed all other parameters as well (Ca, P, etc), the result may be vastly different.
And, of course, if they would have used powerful full spectum LEDs.

Second, regarding "industry averages" - are you kidding me?

Nearly the complete north amercian cannabis industry is using one of the big, cannabis specific nutrients brands released in the last couple years (Athena, Front Row, Floraflex, Chemgro, Cropsalt, Morr, etc).
These guys literally grow millions of plants.
And every single one of this nutrient lines recommends an EC between 2.5 and 3.5 under LED.
Morr even recommends an EC up 4.5 in flower under LED - and this line was created by people at Netafim, after consulting cannabis grows for multiple years and carrying out hundreds or thousands of plant tissue analysis.
In terms of agriculture, you can't be much more "industry" than Netafim.

If you will ever notice that a lot of these lines tell you to not let your runoff EC drop below 5, you will loose your mind. :biggrin:
You can google "pwEC" and go down the rabbit hole...

I tried to check your pics, but nothing in 10 years, and what I saw was mediocre.

Well, ten years ago I was growing in BioBizz under HPS.
But I dont understand your attack - did you even grow ten years ago?

Besides that, I may have not started any threads in the last couple years.
But I didn't cry every couple months that my plants are unhealthy and I cant seem to solve it neither...
You did.
 
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ButterflyEffect

Well-known member
I think we all need to better differentiate whether the grow medium is soil, coco or water. I like soil because it is a huge buffer and can take a lot of abuse. But what is good for some mediums may not be true of the others.
Truth post of the day right here.

Can't tell you how many times I try to put my issue in context with the media I use and still get advice that only pertains to soil. I switched to perlite because, for me, moving bags of soil to where I grow was killing me. Even though I've adapted pretty well to soilless and I personally feel that it's a better way to grow(Strictly my own opinion), I'd go back to soil for the buffering and the plain fact that I'd use less water. I collect rain and I go through 100 gallons a week now so I have to always be conscious of how much I have.
 

ButterflyEffect

Well-known member
First, there is actually a study that found out that more than 240ppm can be detrimental for some strains.

But it's not the study you linked, because as aforementioned, you cant compare hemp (!) grown in soil (!) under the sun (!) with what we are doing here.
And even in the study I'm talking about, they only changed K levels - if they changed all other parameters as well (Ca, P, etc), the result may be vastly different.
And, of course, if they would have used powerful full spectum LEDs.

Second, regarding "industry averages" - are you kidding me?

Nearly the complete north amercian cannabis industry is using one of the big, cannabis specific nutrients brands released in the last couple years (Athena, Front Row, Floraflex, Chemgro, Cropsalt, Morr, etc).
These guys literally grow millions of plants.
And every single one of this nutrient lines recommends an EC between 2.5 and 3.5 under LED.
Morr even recommends an EC up 4.5 in flower under LED - and this line was created by people at Netafim, after consulting cannabis grows for multiple years and carrying out hundreds or thousands of plant tissue analysis.
In terms of agriculture, you can't be much more "industry" than Netafim.

If you will ever notice that a lot of these lines tell you to not let your runoff EC drop below 5, you will loose your mind. :biggrin:
You can google "pwEC" and go down the rabbit hole...



Well, ten years ago I was growing in BioBizz under HPS.
But I dont understand your attack - did you even grow ten years ago?

Besides that, I may have not started any threads in the last couple years.
But I didn't cry every couple months that my plants are unhealthy and I cant seem to solve it neither...
You did.
4.5EC in flower, huh? Not is soil I imagine, though. The buildup would be quite a bit.

Although my plants look pretty damn healthy in flower, I always wonder whether I'm underfeeding. Granted, I run CDM lamps not LED, but I still wonder. My weekly runoff in damn near all perlite is always at least 50% higher than input. I had always assumed that meant that the plants had actually too much food. Being that I feed 3 times a light cycle at 2EC, maybe I am.

That said, you'd think raising the EC to accommodate growing under LEDs would entail only raising certain elements such as Ca & Mg, which seem to be the most affected by the lack of IR/lower transpiration that LEDs cause.
 

Piff_cat

Well-known member
Agreed. Now that I'm getting a handle on the causes, I'll be deploying a controller in my veg room to make sure the environment is dialed in. It's the only room of the four that isn't controlled.
ive been there with veg think we all have lol. since there is so much pressure on grower to avoid problems in flower(rightfully so) veg becomes a "if theyre not dead theyre ok" scenario. i was that way for years.
 

f-e

Well-known member
Mentor
Veteran
Drying pots tend to limit Ca uptake, as it needs fluid movement. If I don't pot up and instead keep running dry, I tend to get hardening of the trunk and red stripes up it. While not generally seen as a Ca issue, Ca delays this. The same signs happen if I go too high with the light, without supporting Ca additions. Some limp leaf in both cases, but notably it's the main trunk stalling.
First, there is actually a study that found out that more than 240ppm can be detrimental for some strains.

But it's not the study you linked, because as aforementioned, you cant compare hemp (!) grown in soil (!) under the sun (!) with what we are doing here.
And even in the study I'm talking about, they only changed K levels - if they changed all other parameters as well (Ca, P, etc), the result may be vastly different.
And, of course, if they would have used powerful full spectum LEDs.

Second, regarding "industry averages" - are you kidding me?

Nearly the complete north amercian cannabis industry is using one of the big, cannabis specific nutrients brands released in the last couple years (Athena, Front Row, Floraflex, Chemgro, Cropsalt, Morr, etc).
These guys literally grow millions of plants.
And every single one of this nutrient lines recommends an EC between 2.5 and 3.5 under LED.
Morr even recommends an EC up 4.5 in flower under LED - and this line was created by people at Netafim, after consulting cannabis grows for multiple years and carrying out hundreds or thousands of plant tissue analysis.
In terms of agriculture, you can't be much more "industry" than Netafim.

If you will ever notice that a lot of these lines tell you to not let your runoff EC drop below 5, you will loose your mind. :biggrin:
You can google "pwEC" and go down the rabbit hole...



Well, ten years ago I was growing in BioBizz under HPS.
But I dont understand your attack - did you even grow ten years ago?

Besides that, I may have not started any threads in the last couple years.
But I didn't cry every couple months that my plants are unhealthy and I cant seem to solve it neither...
You did.
Good post, though some doesn't compute. Such as the runoff expectation. Though I'm sure we were on about K. Hence me posting a study of flower weight at different K concentrations.

I have shown my plants at a bad location. Can you fix them? Plants still beating the industry averages, but not good enough. Would you care to put your good plants up beside my bad ones?

10 years... no. About 5 minutes. Time doesn't teach some people anything. It's just you trying to claim something obscure.

I'm tired of this now. It's the personal angle. We are meant to be taking plants, but you are making sniping comments, after I have already pointed this out.
 

f-e

Well-known member
Mentor
Veteran
I had to get a snap of this after reading about not potting up. I can't use my canna terra range as supplied. I lost two weeks trying on the first canna run. With 44ppm of Ca though, they live, even when there are 15 in a 15 cell tray that should of come out a week ago. I previously thought 88ppm, but was catching up after depleting the terra. Just 44 all the way here
k.jpg


While this look alright for some plant's being kept at bay, I will be back to 88ca for a week or two before transition, then for half of transition. Green loves Ca and it's a good time to get some in. Before K and Mg demand dictate lowering it.
 
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f-e

Well-known member
Mentor
Veteran
That said, you'd think raising the EC to accommodate growing under LEDs would entail only raising certain elements such as Ca & Mg, which seem to be the most affected by the lack of IR/lower transpiration that LEDs cause.
Nearly everyone has found Ca and Mg, but Morr who give both 3.5 and 4.5 mixing schedules, make no ratio change. Keep in mind they say 2.8 with hps/greenhouse. So it's a lot like the 40% extra feed that many of us did when we first switched over. Before bringing the ec back down to find the bits it really wanted.
 
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The Jacks I use is around 7% Mg. I used to add in extra when I started using it, you know 3-2-1? It gave me Ca issues. Now I mix about 25-30%$ of my tanks with well water for the buffering ability and the extra supply. No more added Mg and no more CalMag. Things are looking very good. Time will tell on whether I can get the buildup under control. It would at least save water.
What lights are you running? Led?
 

ButterflyEffect

Well-known member
ive been there with veg think we all have lol. since there is so much pressure on grower to avoid problems in flower(rightfully so) veg becomes a "if theyre not dead theyre ok" scenario. i was that way for years.
Truth. I've had controllers running the environment in my flower rooms for 4 years now. Maybe not fully dialed in, but there. It never occurred to me that my issues in veg were stemming from an inconsistent environment. Lessons learned.
 

ButterflyEffect

Well-known member
Nearly everyone has found Ca and Mg, but Morr who give both 3.5 and 4.5 mixing schedules, make no ratio change. Keep in mind they say 2.8 with hps/greenhouse. So it's a lot like the 40% extra feed that many of us did when we first switched over. Before bringing the ec back down to find the bits it really wanted.
It's not likely I'll switch to LED anytime soon, if at all. I've made my investment in CDM and at this point, a full changeout would make recouping that very difficult. If I were under HPS I probably would make the jump, but the potential improvement of LED over CDM just doesn't make good financial sense. Adding the learning curve and adaptations tips the scale away from upgrading even more.
 

jackspratt61

Active member
I had to get a snap of this after reading about not potting up. I can't use my canna terra range as supplied. I lost two weeks trying on the first canna run. With 44ppm of Ca though, they live, even when there are 15 in a 15 cell tray that should of come out a week ago. I previously thought 88ppm, but was catching up after depleting the terra. Just 44 all the way herew

While this look alright for some plant's being kept at bay, I will be back to 88ca for a week or two before transition, then for half of transition. Green loves Ca and it's a good time to get some in. Before K and Mg demand dictate lowering it.
What's causing the dark green leaves with white midrib,red petioles on older leaves and pooling of dark green at leaf tips?
 

f-e

Well-known member
Mentor
Veteran
What's causing the dark green leaves with white midrib,red petioles on older leaves and pooling of dark green at leaf tips?
I root in coco and it's coming out the rooting environment where they had a wobble. RH transition and moving to terra. The coco rootball is about 25% of otherwise terra filled cell. Here I used terra feed, which is likely a comparability issue. It's certainly not right. The growth while mainly in coco on terra feed and in a lower RH has your attention.

The pooling.. I'm not sure it's real. Some does look a bit like early Fe in the pics, but I think a lot is the lighting. Some above, more from the front, then the flash. I did rush in quick with the full dose feed, changing things up a bit, as it's just my second run. Still a lot of dialing in to do.

These are being held back. I will have them in pots soon. Then I will cut them back and grow them properly.
 

jackspratt61

Active member
I root in coco and it's coming out the rooting environment where they had a wobble. RH transition and moving to terra. The coco rootball is about 25% of otherwise terra filled cell. Here I used terra feed, which is likely a comparability issue. It's certainly not right. The growth while mainly in coco on terra feed and in a lower RH has your attention.

The pooling.. I'm not sure it's real. Some does look a bit like early Fe in the pics, but I think a lot is the lighting. Some above, more from the front, then the flash. I did rush in quick with the full dose feed, changing things up a bit, as it's just my second run. Still a lot of dialing in to do.

These are being held back. I will have them in pots soon. Then I will cut them back and grow them properly.
Nice defined serrations on leaves. I can tell they got N recently.
 

f-e

Well-known member
Mentor
Veteran
They are actually a bit neglected. I take cuts before bloom, ready for the next run. The number I bloom, is based on how big I can grow the cuts, if the cuts are slow.
Excuses aside, I had a better look. There is some darkening towards the tips. Excessive darkening, with a wrinkled look like being in the bath too long. Just in that darker material. I think, though I'm not sure, that I'm looking at Ca excess. The idea of greening plants up with Ca not N is new to me, but people speak of blistered appearance from excess Ca in bloom. I'm just connecting dots, but maybe.
The light is not particularly bright, but maybe 200-250ppfd 24/7 and it's a full dose of terra (in terra) plus the Ca I couldn't grow without on the last run. At the sides in lower light, I have a couple of outdoors I keep alive year to year. They have some downward cupping. A sure sign I'm over doing something. My tap is hard so a bit of N-acid goes in. Leaving me with the old favourite nitrogen, and what's quite new to me, Calcium. Before LED calcium meant nothing to me as a bottled feed user. It was a link you offered that spoke of greening up with Ca I think. Rather than N. Which I didn't even think of as possible.

I think, unless guided otherwise, I will drop the terra a bit. I have also increased all the trace stuff, but not beyond typical bottle quantities of other brands. I did this after the shaky transition from coco cuts to terra plantlets. It's surely N or Ca and it's accumulative appearance and wrinkles seem to say Ca. I'm concerned dropping Ca will be harder to recover from though, and excess may not even be an issue at this time. So will, despite my observations, lower the terra feed.

Thanks for noticing :)
 

Three Berries

Active member
My oldest flowering plant, the test girl now at 25 days into 12/12, on my last application of CaCl2 didn't improve. But the telltale sign wasn't yellow tips on new growth but rather yellowing of the not so new top leaves between the veins. I was expecting a change and anticipating switching to MgCl2.

This yellowing went away with the Mg and or nutes.

So it got some full strength nutes with 2gr Epsom per gallon and a top dressing of ~125ml MgCl2 600 ppm. Responded great. Did the last major defoliate today.
 

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