I’m getting mixed answers when I look up a proper ratio of lime to peat. Maybe one of you could help me out.
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That’s one of those ‘depends who you ask questions’
Generally 1/2 cup to 2 cups per cubic foot.
Here’s a collection of recipes:
soil recipes.pdf (193.4 KB)
Calcium sources have some differences…
Dolomite = Ca + Mg (I think of it as slow release CalMag)
Epsom Salt = Ca + S (quick uptake)
Gypsum = Ca + S (slower uptake but variable)
Crushed shell (egg or oyster) = Ca (slow release)
I use a combination of egg shell and Dolomite with a little Gypsum.
Cheers
G
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I appreciate the resource. I should have clarified I’m trying to make a soilless mix. Are you familiar with calcitic lime? Does it have the same elements as dolomite? I know calcitic is fast release and dolomite is slow release that’s why I got both.
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Yes, regular garden lime, calcium carbonate. It’s just a Ca source.
I don’t see that used in the organic soils. I recall “Total Living Organics” warned away from it. I think it was pH fluctuation, but they liked the Dolomite.
I recall that the plants preferred a ratio of 1:2 Ca:Mg (IIRC 
)
Cheers
G
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Cal mag ratio is 2:1 Cal/Mag
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Yeah i was always going for 1 cup per cubic foot of a mix of 2-1-1 Dolomite, gypsum, calcium carbonate…always perfect!
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Dolomite contains 5% minimum Magnesium. Calcite contains 5% magnesium maximum, 30% calcium minimum.
One brand of dolomite can be 5% mag 29% calcium. One brand of Calcite can be 4% mag 30% calcium. How is that different?
Pot growers need to get past labels. Like, flip the package over and read the other side maybe.