Issues getting Ag Lime: will Dolomite and Gypsum be enough?

Hello RIU.

I'm facing some trouble with the lime content of my recipe.

I want to go with mixes like Coots and others than go with some type of lime which is mostly Calcium Carbonate, like higher than 95% CaCO3.

But i can only seem to get Dolomite Lime. The one i can get is 60% CaCO3 and 40% MgCO3.

I know that Dolomite is used, and already used it myself, but it's clearly a big difference both in CaCO3 % and Ca:Mg ratio comprado to Agricultural Lime.

I bought some medium grind oyster shells and will try to get them to a flour like consistency to solve the problem, but on the meanwhile i wanted to know your opinions on the subject.

Original plan is:
1 cup per cubic feet of Calcium Carbonate
1/2 cup pelletized gypsum

Guess that with Dolomite i would/should bump the Gypsum up to 1 cup, right?

On the other hand, here is a GroKashi link were DOlomite is used: http://gro-kashi.com/?page_id=8
So i don't know what to believe comparing that recipe to Coot's mix.
Best option would be to have my soil tested, and it's something i want to do, but right now im pretty short on money and by experience i know that my soil mix lacks Calcium; last time i amended it with 1/2 cup of Dolomite per cubic feet.

Dolomite lime and gypsum will work fine. That's what I use, and I've never messed with the other lime. Like 10 years ago people used to say that Ag lime would kill your plants and that you should never use it.

Some of the amendments you might use for Phosphorus like crab shell, bat guano, or fish bone also contain calcium, so you don't have to worry about the lime being your only source.

youraveragehorticulturist said:

Dolomite lime and gypsum will work fine. That's what I use, and I've never messed with the other lime. Like 10 years ago people used to say that Ag lime would kill your plants and that you should never use it.

Some of the amendments you might use for Phosphorus like crab shell, bat guano, or fish bone also contain calcium, so you don't have to worry about the lime being your only source.

Click to expand...

All I use is Dolo, which avoids Mg issues down the line. This is strictly for pH @1cup/cf. I also use crustacean meal, gypsum, ect for other purposes. Gypsum has little effect on pH (wrong form of Ca (Sulfate not carbonate), but is a good source of calcium.

Pure Calcium carbonate is fine, but then you need to find a source for Mg and adding Epsom Salts gets to be a pain.

Wet

Thanks to both, will go with the Dolomite Lime and gypsum