Your Preferred Calcium/Magnesium Sources

I have a severe magnesium def and a calcium def too. What's your preferred brand of CAL MAG? Do you prefer to mix soil amendments containing calcium and magnesium in with your soil to begin with? If so, what do you use and what are your results?

Thanks in advance for your replies.

This...an organic source anyway

Yea that one is one that i am considering. They sell it my local shop, and i prefer organic.

Always add dolomitic lime to your potting mix, which will help eliminate cal/mag deficiencies. Buy the powdered type, as fine as you can find it- so it breaks downs easier and faster. I use 3.75 cups per 3.8 cu. ft bale. It also helps keep the pH up and offsets the fertilzer (which is a salt) which drives the pH down.......

Hows aboot some more opinions, eh?

Epsom salts for Mag.
Water from hot water tank for Cal.
Cheap.
Never really understood the whole cal/mag thing. Does everyone who gets a deficiency of one get the other too? Makes no sense to me.
Especially when an Iron deficiency looks so similar.

I was actually considering using the hot water for the mineral content! I think they are both used heavily in fruiting/flowering plants. If you have too much calcium, it can lock out the magnesium, so i like the idea of using a cal mag formula where there is no guesswork. That's why i'm hoping to get a lot of people voting on the poll, so i can know what works for people in the real world.

Cobnobuler said:

View attachment 2404925This...an organic source anyway

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organic "Based". Have to read the labels carefully.

Many people use an r.o. water filter, which removes most of the cal and mag (and most everything else) so they can start with neutral water. If your starting ppm is over 350 or so, a r.o. device should be used. Therefore, you would have to add extra cal/mag to make up for what was removed.

I don't use RO water, but i use rainwater, which i would think would have less mineral content than ground water/tap water. I plan to try my hand at hydro next year, starting with some tomatoes, and once i do, i will invest in meters so i can tell my water's PPM. For now, i just use my aerated rainwater, but i still developed a pretty bad mag def.

Rain water is typically very acidic, which leads me to think your problems are more pH related..........

CSI Stickyicky said:

I was actually considering using the hot water for the mineral content! I think they are both used heavily in fruiting/flowering plants. If you have too much calcium, it can lock out the magnesium, so i like the idea of using a cal mag formula where there is no guesswork. That's why i'm hoping to get a lot of people voting on the poll, so i can know what works for people in the real world.

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That's my point. You aren't removing the 'guesswork', you are adding to it. Excess phosphates also lock out Mg. It's all about a balance. I really don't know how cal-mag became popular other than to rectify faults caused by bloom busters etc. A fault that probably wouldn't be there in the first place with a decent, 'normal' nute schedule. Unless you listen to the people at the shop and buy the latest line of crap that is intentionally missing things to make you spend more cash on their over-priced crap.
I have had a magnesium def only one time.
Remember this and remember it well.
It's not about 'boosting, turbocharging' or whatever. A plant will take what it needs, no more. Too much of one element will often result in problems absorbing another. Give our babies what they NEED, no more.
Understand that a lot of people are out there trying to sell a load of crap to convince you otherwise.
Then, KARMA.

Yea, i really need to get a good ph meter.

The drop kits are good. I spend £4 for 2 years worth (pH essentials)
and no calibration worries

Use Bonicare and GO..I think GO has more calcium. Just whats cheap..lol Dolomite in the soil.. No calmag issues. Tbsp to gallon of soil.

And waiting for the peeps trying to sell us crap. It will come.....Or have I shut them up?

The reason i have a def is because i am using a really small container, and i didn't fertilize with anything, so it's just simply used up what's in the soil. All of the plants that i tried flowering in one gallon pots (an experiment) developed a mag and a phos def right as it went into aggressive flowering. I top dressed with high phosphorus bat guano for the phosphorus deficiency, but i need a soluble cal mag to fix the cal and mag deficiencies. In the future, i'll use 3 gallon pots, and mix in dolomitic lime and azomite, maybe make subcool's super soil, but now i have the cal-mag in my toolbox to fix future deficiencies.

For now, i foliar fed with epsom salt and water, and i will add Botanicare's Cal-Mg Plus next watering. In the future, i will use fertilizer or compost tea as needed.

General Hydroponic Calimagic - because it has 0.5% more Mg in it than the alternative I can buy and 1% less Nitrogen. Coco is a real Mg consumer, it has strong affinity for it. Hence a slightly higher concentration being my preference.

I've also seen people use Epsom Salts in their Coco only to seriously regret it later.

I just stick with what I know works I guess.

I grow my bonsai chillis and basil in coco with no problems so far. They are the only plants I grow in coco and the only ones I haven't had to add mag to.