DIY CalMag+ style (calcium and magnesium with iron) supplement

CalMag Plus is a vital part of growing marijuana, and you can make your own comparable version easily for a fraction of the price of commercially available ones. This is a highly fortified calcium, magnesium and iron plant supplement that is designed to correct common deficiencies.

77.83 grams of Calcium Nitrate
77.83 grams of Magnesium Nitrate
7.89 grams of 13% Iron EDTA
1 quart of distilled water

soil gardens: 4.75 ml per gallon of water
hydroponics: 9.5 ml per gallon of water


These recipes are awesome. Do you make your own base nutes too? Also do you have one for pure (or almost pure) phosphorus?

1 Like

Triple superphosphate. 0-45-0

“TSP”. Very cheap.


I actually got some. Unfortunately it’s in pellets and not readily available to plants…it’s more like the stuff you throw around your lawn in spring. Even ground up and dissolved in water it just caused issues for me.

Here’s a handy list of common P sources, solubility, etc. They’re all very cheap:


Are these ingredients readily available at my locale shoppe?

1 Like

Agricultural store, large hardware supply, greenhouse supply, and on the internet.

Don’t order too much ammonium nitrate though lol due to “past incidents”.


Yeah, tim mcvay…or whatever, whomever.
I used to do landscaping…had pallets of it at my disposal. Never thought of joining ISIS until I saw how cool Syria was on 90 day finance …I joke, I joke …Allah akhbar

Edited again…how insensitive was that remark…fuck…


LOL growhard turned me on to 90 day fiance and I can’t stop watching the trainwreck haha

The fuckin’ guy who knocks up that Amazonian girl and runs away into the woods every time he gets upset…


Would you fuck Darcey?..totally, right!!!
…I mean, if you were single…


Asuelo or whatever…that douche who wanted to bring his kids to a measles hotspot?

Edit…oh shit…#90dayfiance thread!!!


That’s a great link, thank you.


I have indeed, however that is a much more complicated process, and the recipes can vary depending on the quality of your sources, etc… There are plenty of other folks who can tackle that arena better than I can. There is also the free HydroBuddy software to help with that. I am glad you are enjoying the recipes I have posted and I hope that they help you save some money as well as take more personal control over your plants needs.


Same parts of calcium nitrate and magnesium nitrate?,

not is: one part of magnesium for 2 part of calcium?,

no to much Nitrogen and exess of magnesium block potasium?

that’s the correct ratio - and it seems to work for me just fine without blocking anything. As others have pointed out this exact recipe is popular, and has been well-tested with these ratios

1 Like