Cal/Mag supplement for soil grows?

[SirTokesIt]

Hi, I started a grow using LEDs to veg for the first time... I was told I had to use cal/mag just because I went from using CFLs for veg and HPS for flower to using LEDs for veg.
I've read all kinds of stuff about cal/mag and LEDs for hydro and such but can't find anything about whether I need it or not using soil? Any help would be appreciated.

 

[Robert Celt]

Some members have noticed that their plants under LEDs required more Cal/Mag. I did not have that issue with my girls under LEDs but I use an organic soil and my amendments may have had excess Cal/Mag not sure. You could add some ground egg shells and Epsom salt to your soil to hedge your bet, or wait and see if they show signs of deficiency.

 

[madsdad4ever]

a little dose wouldn't hurt it anyway

 

[MassMedMan]

Some members have noticed that their plants under LEDs required more Cal/Mag. I did not have that issue with my girls under LEDs but I use an organic soil and my amendments may have had excess Cal/Mag not sure. You could add some ground egg shells and Epsom salt to your soil to hedge your bet, or wait and see if they show signs of deficiency.

Same here, I didn't use much cal/mag in my recent grow with LED's. But, my soil is designed with that in mind, at least the Coast of Maine Stonington blend I was running.....

 

[SirTokesIt]

Thank you all! I think I'll buy some just to have it on hand... if I need it then, no worries.

 

[Dave Groomer]

Thank you all! I think I'll buy some just to have it on hand... if I need it then, no worries.

I add 10ml cal/mag to every gallon of water.

 

[fanleaf]

I on the other hand am just finishing my battle with a mg deficit under my Advanced 300W LED. I use distilled water so I expected to have to supplement but being a new grower I didn't recognize the signs near as early as I should have. I guess you live and learn righ?
My AK47 had it pretty bad. To the point that growth was stopping but I think I am recovering now. I foliar sprayed her with a dose before lights on and fed the soil as well. This morning seen all leaves standing up at attention the way they should be. Looks like about a half inch of growth last night too.
That was close though. I would have hated to lose this beauty due to mag when I have plenty sitting on hand. Shes getting close to a month old from breaking soil and shes spitting hairs

 

[SirTokesIt]

I add 10ml cal/mag to every gallon of water.

supergroomer, Thanks. I went to your journal and see you're in soil as well. I have a question not related to cal/mag... .I noticed your LED light and wondered how high above the top of the plants you try to keep it? I'm wondering if mine are too close? Thank you.

 

[SirTokesIt]

fanleaf,
Thank you for the info!

 

[Dave Groomer]

18" or so seems to be the sweet spot in flower. With the Mars lights, you need to be far enough away to get the "blending" of the different spectrum from the different LEDs. If you get too close you loose that. I probably wouldn't go closer then 14" or so. In my veg tent, I have them closer to 24" for maximum coverage.

 

[Robert Celt]

Hey guys, like Super I try to keep my 900 about 18" from the tops. I don't have a PAR meter but tests with my light meter showed that the best intensity was in the 18" to 26" range. Keeping the light at 18" from the tops gives you about 8" of optimum penetration

 

[SirTokesIt]

18" or so seems to be the sweet spot in flower. With the Mars lights, you need to be far enough away to get the "blending" of the different spectrum from the different LEDs. If you get too close you loose that. I probably wouldn't go closer then 14" or so. In my veg tent, I have them closer to 24" for maximum coverage.

supergroomer, thanks for that.... I just grabbed a tape and measured... my LEDs were 7 inches above the tops of my potted clones!! They're now right at 18"!! Thanks again.

 

[Dave Groomer]

supergroomer, thanks for that.... I just grabbed a tape and measured... my LEDs were 7 inches above the tops of my potted clones!! They're now right at 18"!! Thanks again.

I think you should start seeing even better growth.

 

[SirTokesIt]

I think you should start seeing even better growth.

supergroomer... wow! You hit it on the head bro!! I'm seeing new growth already.
Your logic about the colors not mixing properly up too close made perfect sense.... thanks again.

 

[MassMedMan]

I on the other hand am just finishing my battle with a mg deficit under my Advanced 300W LED. I use distilled water so I expected to have to supplement but being a new grower I didn't recognize the signs near as early as I should have. I guess you live and learn righ?
My AK47 had it pretty bad. To the point that growth was stopping but I think I am recovering now. I foliar sprayed her with a dose before lights on and fed the soil as well. This morning seen all leaves standing up at attention the way they should be. Looks like about a half inch of growth last night too.
That was close though. I would have hated to lose this beauty due to mag when I have plenty sitting on hand. Shes getting close to a month old from breaking soil and shes spitting hairs

I'm a fan of Sea90 for a cal, and mag supplement. One thing you can think about for the future. You'll get cal and mag plus a shit ton of trace elements.

From the sea, can't go wrong.

I put a tablespoon in the soil of each can, except when I'm on Doc's kit, and then once in late veg, and again in mid bloom I give them a good foilar mist, and for added kick I throw in a cap full per gallon of some Neptune Harvest.

I've read a lot of stuff on cal mag, and frankly I'm not convinced it's the best solution.

One of them, but,,, that's my two cents.

 

[Dave Groomer]

supergroomer... wow! You hit it on the head bro!! I'm seeing new growth already.
Your logic about the colors not mixing properly up too close made perfect sense.... thanks again.

Glad to help!!!