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Grittyville, WA

https://www.gardenmyths.com/diy-cal-mag-fertilizer/

This seems like the way to go the internet is obsessed with eggshells, I dont get how the plants are supposed to use them unless they are dissolved.

3/26/2023 4:43:45 AM

Syracuse, NY

Yes, it seems to be fully explained below - careful to read closely the items described as perhaps fallacies - there should have been a colon (:) placed before them,
like 'Here - Don't do these:'. eg

3/26/2023 11:32:52 AM

Roseville CA

ORRRRR you can just mix some Calcium Nitrate and Epsom salt and you got Cal-Mag!!!

If I did the calculations correct, if I mix 8 pounds of Calcium Nitrate and 6 Pounds of Epsom salt in 1 gallon of water, I get a gallon of Cal-Mag.

Not only do I get 1 gallon of it, for less than 15 bucks, but I also get a fertilizer that is 14-0-0, has 19% Calcium, and 8% magnesium. Considering that commercially available Cal-Mag has 1 percent magnesium. This is 8x as much power and is almost equivalent to 8 gallons of commercially available stuff.

To get around 200 dollars of Cal-Mag, I think this will make the same amount for about 15 bucks.

3/26/2023 2:59:58 PM

Grittyville, WA

That sounds good. At some point you might end up creating gypsum, which would have low solubility, but on the flipside, gypsum is super cheap and used copiously by some of the top growers... and thats where my knowledge runs out.

3/26/2023 3:05:57 PM

Lodi, California

Cal mag is literally just calcium nitrate and magnesium sulfate mixed in water. They are literally selling you water. You can pay $80 for water, or you can pay $80 for 50 pounds each of calcium nitrate and magnesium sulfate, and have enough to make about 50 gallons of cal mag solution.

3/26/2023 3:06:28 PM

Seattle, WA

Dolomite might get you there too if you have a low pH.

5/1/2023 3:14:03 PM

Millville, UT

every fertilizer compatibility chart I have ever looked at says calcium nitrate and magnesium sulfate shouldn't be mixed together. It says they form insoluble calcium sulfate which I am assuming would make the calcium unavailable to the plant.

8/5/2024 5:29:05 PM