plant ph and mag Issues after switching to cobs

Greengenes707 said:

Hey man,

You can work with it, but it might not be the best for replicating canna.

Here is canna coco with and without the PK boost...
View attachment 4043950

I can not really replicate canna with it. Either veg or flowing canna.
You can replicate(I say this loosely) the canna w/PK with it if you also get some MPK
View attachment 4043956

But can make some good basic ratio feeds with it, but all will be lower on in P than other mixes if you play around on the calculator with it. I have a video series planned for nutrients and all the calcs, just need my space back from my remodel. But if you get some MKP, you can make about anything you want.

Here is something close to jacks and what I run with your stuff...
View attachment 4043959

And here is the same with a little MKP in the mix...
View attachment 4043960

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Great information @Greengenes707 !
Question - do you hear of many running Canna Coco getting Mag Deficiencies?

Cal Mag deficiencies under LED have been reported a lot. What, exactly, about LEDs is making plants deficient in these minerals? Do these deficiencies also appear under "blurple" LED and full-spectrum white LED the same way? Could it be due to the lack of UV spectrum?

tstick said:

Cal Mag deficiencies under LED have been reported a lot. What, exactly, about LEDs is making plants deficient in these minerals? Do these deficiencies also appear under "blurple" LED and full-spectrum white LED the same way? Could it be due to the lack of UV spectrum?

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LED does not warm the leaf surface as much (less IR). This reduces transpiration. Cal and Mag are brought into the plant through transpiration. If you bring your ambient temps up the plants tend to do better under LED.

mcnasty_nug said:

final update. It seems the problem is solved. Getting my PH under control by lowering the times the air went on, and bumping up the mag to the doses I posted earlier has solved it. Plants leaves are all nice and green again. Thanks again to everyone who took the time to help me out. Much appreciated.

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Great to hear man!!! Love getting to the bottom of shit like that. Honestly this thread could help a lot of folks. Thanks for staying civil everyone.

Interesting @nfhiggs! Thanks!

The savings in the efficiency of LED over, say, HPS or MH, is somewhat negated then, by the need to add heat to the growing space in order to bring the transpiration rate up so that the plant can uptake the CalMag. That's great if you grow in a naturally warm area year-round -clear advantage to LED in the warm-weather scenario. But if you live further North and/or prefer to grow during the colder months so as to avoid vectoring in warm-weather-outdoor pests, then you might be better off to just stick with a less-efficient form of lighting that has more IR and gives you more of an all-in-one light/heat source -and one that also has more UV spectrum, as well.

tstick said:

Interesting @nfhiggs! Thanks!

The savings in the efficiency of LED over, say, HPS or MH, is somewhat negated then, by the need to add heat to the growing space in order to bring the transpiration rate up so that the plant can uptake the CalMag. That's great if you grow in a naturally warm area year-round -clear advantage to LED in the warm-weather scenario. But if you live further North and/or prefer to grow during the colder months so as to avoid vectoring in warm-weather-outdoor pests, then you might be better off to just stick with a less-efficient form of lighting that has more IR and gives you more of an all-in-one light/heat source -and one that also has more UV spectrum, as well.

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I think it depends on the feasibility of getting the environment under control. If it's not too much money or work, why not take steps to keep your growing climate optimum for the more efficient lighting source? But if it's going to require a remodel and investment in a bunch of climate-control gear, the potential savings you get from energy-efficient LEDs begin to shrink, if not disappear altogether.

But of course this conversation is flipped if we're talking about growing inside during the summer. Even in the frozen north (Michigan), we get oppressively hot summer weather. Running AC isn't exactly ideal either.

If you are in a cold area...think about sealing that bitch up and pumping the C02...and using every bit of energy(in light and heat) that a top LED system can offer.
You win on many fronts that way. If your outside ambients are freezing...no AC sealed room is totally do able...I've done it. May take some toying with the insulation levels, but half the year you would be running damn near free for cooling.

tstick said:

Cal Mag deficiencies under LED have been reported a lot. What, exactly, about LEDs is making plants deficient in these minerals? Do these deficiencies also appear under "blurple" LED and full-spectrum white LED the same way? Could it be due to the lack of UV spectrum?

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I have the same questions. I also have more. There are actually physiological changes to the plant itself from the cob lights.

I've done 2 Cob runs. Both ran into deficiencies. Both runs the lower buds were rock hard. Just as hard as the tops. When all was trimmed in dried. I noticed that the density was higher in the nuggets. And that is where the extra weight is. And when I say denser I don't mean that the calyxs grew tighter together. I mean that the actual plant matter that forms the calyxs we're thicker and harder. Like when you use silica. It's like the cellular structure is more beefy. I also noticed that the stems we're more brittle.

When chopping nugs up to roll one up they seemed very brittle. Some even bursted in the scissors. Where does that brittleness come from?

I also noticed that there was more resin production. And that the resin was more flavorful.

tstick said:

Interesting @nfhiggs! Thanks!

The savings in the efficiency of LED over, say, HPS or MH, is somewhat negated then, by the need to add heat to the growing space in order to bring the transpiration rate up so that the plant can uptake the CalMag. That's great if you grow in a naturally warm area year-round -clear advantage to LED in the warm-weather scenario. But if you live further North and/or prefer to grow during the colder months so as to avoid vectoring in warm-weather-outdoor pests, then you might be better off to just stick with a less-efficient form of lighting that has more IR and gives you more of an all-in-one light/heat source -and one that also has more UV spectrum, as well.

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no totally true. I live north, its cold as hell right now. With all HPS I needed to run MAJOR fans to keep the room temp down. With the LEDs I just exhaust them right back into the room to keep the temps where they need to be. The heat produced by my leds seems to keep the room in the low to mid 80s. In the warmer months, I didn't need any cooling. I simply exhausted most of the LED hoods out into the attic with a single 8" fan. As opposed to HIDs needing several fans AND an ac.

Although, I am considering mixing some CMH 315s in simply so I don't have to worry so much about this type of thing. We'll see how this grow goes and if I run into issues again