Need Information on Cal/Mag Deficiencies When Using Led Lights

BB Boomer

Well-Known Member
I am not getting a Cal issue, it has only been Mag def. Got tons of Cal in my hard water. I have got the Mag issue under control now though. I am on a new grow but the Mag issue showed up again within a week of going under the led and were vegged under T5's. Turns out I was keeping the soil a bit too wet compared to when using HPS and I use a epsom salt foliar now at the first sign of a Mag def . I also gave a dose of General Organics CalMag but that instantly gave me a nitrogen toxicity most likey due to the fact I am growing in a super soil that already has allot of nutes in it. I did a flush and the girls perked back up. Going to go with Earth Juice Microblast next time since it doesn't have any nitrogen.

My 2 cent, I've switched over from HPS, and it has been rough. So far had a Mag issue, then the plants drinking more then eating, causing really high run off PPM's, then a flush really hurt the roots. SO now everything is limping along.
I feel like I am right in the boat with you brother.

I'm solving the watering issue tonight by installing a Blumat system. I have always been a fan of lifting the pot to judge when to water but between scrogging now and the idea of watering according to the actual need of the plant it just seemed to make sense to spend the coin.
 
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Los Reefersaurus

Well-Known Member
I'm solving the watering issue tonight by installing a Blumat system. I have always been a fan of lifting the pot to judge when to water but between scrogging now and the idea of watering according to the actual need of the plant it just seemed to make since to spend the coin.[/QUOTE]

Us fools seldom differ I am picking up my special order BluMats tomorrow lol.
 

theslipperbandit

Well-Known Member
If u look at my thread you can see what they can do n my girls were nice n green, I'd 2gg4 dbxl3 and dbxl6 (rip 6) and I intentionally didn't lollypop to see her penetration n if u look at the thread you'll see beasts n I'd not hung the lights off the tent frame n had light burn so now this run they're on my frame as suggested amd I'm very pleased
 

BB Boomer

Well-Known Member
Hi Slipperbandit.
I took a look and how lush the canopy looked and marked the thread for reading. If you are doing that it bears worth doing the same since that is just the kind of lush green I am looking for. I don't have a cob set up though. I sold my first born and bought a Apache AT600. Still trying to figure out how far to keep from the canopy. I bought both sets of lenses for it too and even after switching to all 50 degree lenses from the 14 degree lenses it seems I can't get any closer than 3.5 feet for sativa/indica hybrids and 3 feet for straight indicas. I read in another thread that I should be able to get 2 feet away or even a bit closer with all 50 degree lenses so go figure. It is a serious powerhouse light though. The highest wattage light I used before this was a 600 watt hps. Getting the distance down will be the next problem to tackle after I am more confident I have the Mag issue dead and buried. Until then I will go with what I have figured out so far.The new grow is only about a week and a half into flowering so there is plenty of time left to get things figured out. I am optimistic, I already have things going a little smoother than last grow so I will continue to research, grin & bear some old fashioned trial & error and look forward to when things become routine again where every grow turns out perfect with no annoying problems to deal with along the way.
 

sethimus

Well-Known Member
@wietefras it's because LEDs aren't putting out the spectrum your plant needs so it develops a deficiency, no LED is full spectrum, they are either a blue diode sprayed with a phosphor coating or a bunch of colored diodes that are combined to imitate white light, none of them actually produce a true full spectrum light ,they are all targeted spectrum even the white light LEDs.

If you used blurple leds the problem would be even worse. Blurple LEDs can't even grow lettuce good, the color is terrible for the plants and makes them look ugly and tip burn.

Plant's developed over billions of years to grow with the sun's spectrum, which is a ball of burning gas. There is no burning gas in an LED diode.

It's why if you go from a 250w hps to a 1000w hps you wouldn't have the same issue you are having. This problem has nothing to do with light intensity or par or anything it has to do with the crap spectrum LEDs produce. It's the main reason i no longer use my LEDs as a main grow light, they are best used as a supplemental light.
 

wietefras

Well-Known Member
@wietefras it's because LEDs aren't putting out the spectrum your plant needs so it develops a deficiency, no LED is full spectrum, they are either a blue diode sprayed with a phosphor coating or a bunch of colored diodes that are combined to imitate white light, none of them actually produce a true full spectrum light ,they are all targeted spectrum even the white light LEDs.
The spectral distribution inside the PAR range has no influence on calcium uptake. Calcium is taken up passively. So it's uptake is in proportion with the evaporation of the plants. Under HPS the evaporation is higher than with leds (due to the heat radiation of HPS).

Indeed what the sun does have in common with HPS is the heat radiation. For outdoor plants that will also help with calcium uptake.

I don't see the problem with adding some calcium or calmag. Lots of people even find they need to add calmag when using HPS lights. So it's just whats in the nutrients in relation to what the plants need. It differs per strain even. With some nutrients (with higher calcium content) you probably never will see a calcium deficiency under leds. Also people already adding calmag by default.

If you used blurple leds the problem would be even worse. Blurple LEDs can't even grow lettuce good, the color is terrible for the plants and makes them look ugly and tip burn.
The problem with burples is that they only activate the chlorophyll pigments for photosynthesis.

If you want to use the high light intensities like we use for growing weed then using only a part of the plants systems means that part will get overloaded quite easily.

With full spectrum lights you use all the pigments:

PlantPigments.jpg
Of course if you are using only supplemental lights then burple is fine. Lots of greenhouses use burples for supplementing sunlight. Also when you grow on lower light intensities you wont overload the chlorophyll.
 

Yodaweed

Well-Known Member
The spectral distribution inside the PAR range has no influence on calcium uptake. Calcium is taken up passively. So it's uptake is in proportion with the evaporation of the plants. Under HPS the evaporation is higher than with leds (due to the heat radiation of HPS).

Indeed what the sun does have in common with HPS is the heat radiation. For outdoor plants that will also help with calcium uptake.

I don't see the problem with adding some calcium or calmag. Lots of people even find they need to add calmag when using HPS lights. So it's just whats in the nutrients in relation to what the plants need. It differs per strain even. With some nutrients (with higher calcium content) you probably never will see a calcium deficiency under leds. Also people already adding calmag by default.

The problem with burples is that they only activate the chlorophyll pigments for photosynthesis.

If you want to use the high light intensities like we use for growing weed then using only a part of the plants systems means that part will get overloaded quite easily.

With full spectrum lights you use all the pigments:

View attachment 3929100
Of course if you are using only supplemental lights then burple is fine. Lots of greenhouses use burples for supplementing sunlight. Also when you grow on lower light intensities you wont overload the chlorophyll.
IR light is part of the lighting spectrum, therefore this is a lighting spectrum problem. This only is happening to people using LEDs as well and a quick google search can confirm that multiple people on multiple forums have this exact same problem when switching from HID to LEDs, so through process of elimiation this can be directly attributed to the spectrum these lights produce, the chart you listed confirms this and shows why blurple are the worst when it comes to cal/mg problems. The metabolic rate will be screwed up, the plant tries to adapt, you get this calmg problem from that. Hopefully we can one day fix the spectrum of these leds because they are way more efficient than hid lights.

I also like to say there is a lot of vested interest on this section to make LEDs look better than they are, i wish we could just be honest with each other and stop all the bickering when someone doesn't agree with another person or shares a different experience.
 

theslipperbandit

Well-Known Member
Hi Slipperbandit.
I took a look and how lush the canopy looked and marked the thread for reading. If you are doing that it bears worth doing the same since that is just the kind of lush green I am looking for. I don't have a cob set up though. I sold my first born and bought a Apache AT600. Still trying to figure out how far to keep from the canopy. I bought both sets of lenses for it too and even after switching to all 50 degree lenses from the 14 degree lenses it seems I can't get any closer than 3.5 feet for sativa/indica hybrids and 3 feet for straight indicas. I read in another thread that I should be able to get 2 feet away or even a bit closer with all 50 degree lenses so go figure. It is a serious powerhouse light though. The highest wattage light I used before this was a 600 watt hps. Getting the distance down will be the next problem to tackle after I am more confident I have the Mag issue dead and buried. Until then I will go with what I have figured out so far.The new grow is only about a week and a half into flowering so there is plenty of time left to get things figured out. I am optimistic, I already have things going a little smoother than last grow so I will continue to research, grin & bear some old fashioned trial & error and look forward to when things become routine again where every grow turns out perfect with no annoying problems to deal with along the way.
Here's my girls now just after a foliar epsom feed sorry about the lighting I tried to adjust best I could
noexif_09e525c6.jpg
 

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theslipperbandit

Well-Known Member
I've not topped the dbxl3 as last time she didn't like it so I pinched those higher branches and tbh I'm glad I kept her as a mate said she tasted better than my prized dbxl6 n she's keeping up with the exo but this is only a few days into flowering so well see
 

theslipperbandit

Well-Known Member
Yeah but just a few days ago, stretch is strain dependent so I'm expecting the exo to explode but my dbxl3 is showing promising Signs just gotta rub the larger branches n angle em where they should go lol
 

BB Boomer

Well-Known Member
Great pics! Any info on how often you apply the foliar and what is your mix rate? I will be reading your thread tonight after I get my outside house chores done. I installed the Blumat system last night so I'm tickled about that. I also have their moisture meter on the way. It was shipped a week ago but they tied it to the back of one of their slower tortoises so I am still waiting.

It's the main reason i no longer use my LEDs as a main grow light, they are best used as a supplemental light.
I can't say I haven't had the urge to cut my losses and do the same but since I have a considerable amount of money invested now I am determined to make it work although I still have all of my hid equipment. If all it takes is supplementing some Mag or Cal/mag that really is easy enough to do.
Better yet, I'll just put Slipperbandit in charge of my garden and take a vacation. What you say? You can manage a commute, right?
 

BB Boomer

Well-Known Member
Great pics! Any info on how often you apply the foliar and what is your mix rate? I will be reading your thread tonight after I get my outside house chores done. I installed the Blumat system last night so I'm tickled about that. I also have their moisture meter on the way. It was shipped a week ago but they tied it to the back of one of their slower tortoises so I am still waiting.
 

BB Boomer

Well-Known Member
I'll put up with that kind of sickliness.

Since going through this thread I am less frustrated. I thought maybe I went brain dead and forgot how to grow. I didn't know if my def problem was a true def or a lock out problem not to mention the cause. Now that I know I am not alone in having these problems and seen inspirational success stories I know there is light at the end of the tunnel. It is just a matter of sharing information and applying what I have learned.
 
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