Know about lime? Calicum Carbonate, Magnesium Carbonate?

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ezenzyme

ezenzyme

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Who knows about Lime?
There are a few different limes available and used in agriculture; Agricultural lime is ground Calcium Carbonate i.e limestone, the interwebs says good stuff will have around 37% calcium in it. Calcium Carbonate is primarily composted of Calcium, Carbon and Oxygen. There is not a significant amount of Mg in Calcium carbonate. Calcium Carbonate reduces the acidity of your soil making it more basic.
The second one used is Dolomite Lime. Dolomite lime is calcium carbonate mixed with magnesium carbonate to add the Mg boost.
So who knows about this stuff? The questions that pop into my mind are;
With proper use will Dolomite lime eliminate the need for Cal Mag? If my PH is pretty good will the use of Lime drop it beyond where i want it? How long will Lime buffer the soils PH?
 
mysticepipedon

mysticepipedon

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The use of dolomite lime might eliminate the need for Cal/Mag, but not necessarily. You add liming materials (calcite or dolomite) to adjust pH. Sometimes, adding enough Mg to satisfy a plant's needs will make your pH too high. But in an organic soil grow, the hope is that you don't have to add Cal/Mag (but I always have it on hand).

If your pH is good, liming materials will raise pH, generally into the 7s. If a soil pH is 8 or higher, it is likely caused by an abundance of sodium.

Lime will buffer soil pH until it dissolves completely. It depends on how finely ground the liming material is and the Calcium Carbonate Equivalent (CCE) of the liming material. Pure CaCO3 has a CCE of 100. It is a comparison of the acid neutralizing ability of the liming material compared to pure CaCO3.

Aside from pH, too much CaCO3 can make other nutrients unavailable to plants by either combining with that nutrient (Ca combines with P to form insoluble compounds, and the P is then locked up and can't be used by plants, for example.)
 
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Homesteader

Homesteader

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I would highly recommend looking into replacing lime with gypsum. You can supply both calcium and sulfur and increase your quality. Carbonates are a pain in the ass. I try to use them as little as possible.

If you want to learn a bit about lime, here is a link.
 
ezenzyme

ezenzyme

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I would highly recommend looking into replacing lime with gypsum. You can supply both calcium and sulfur and increase your quality. Carbonates are a pain in the ass. I try to use them as little as possible.
Why do you avoid carbonates? Does Gypsum have the same effect on PH?
 
Homesteader

Homesteader

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Gypsum doesn't effect the pH really. I usually get my pH correct by adding the correct amounts when making a base. Coco and peat in a 50/50 will get you around 6.0pH generally.

When it comes to carbonates it kind of depends on your water source. If your water is good and free of many carbonates than adding lime isn't going to be a big deal. Its the lime + the treated water people use that seems to be the pain in the ass.
 
Homesteader

Homesteader

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Argonite (Oyster shell) is about 33% calcium
Calcite Lime is 87% calcium 7% magnesium
Dolomite is 53% Calcium and 42% magnesium
Gypsum is 21% Calcium and 17% sulfur.
 
Grapefruitroop

Grapefruitroop

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When i buffer raw peat i use a mix of 2 part dolomite 1 part gypsum and 1 part calciumcarbonate....one cup of this mix xcubic foot
A little bit of everything!
In my case i still have to use a LOT of calmag cause...indoor...led....co2..
 
mysticepipedon

mysticepipedon

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Yes, it all depends on the soil mix. Peat, by itself, is pretty acidic, so I always put some dolomite in to adjust it.

Where I used to live, I needed a lot. Now I live in an area where the tap water has a pH of 7.1-7.2, so...
 
ezenzyme

ezenzyme

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Homesteader, your talking about hard water? Or the chlorine/clorimide treatments water gets? And what issues arise from that? The water i am using comes out right around 7.0 ph and is pretty low ppm of 120, but also i see white stuff building up on the bottom of my tank i am assuming is calcium. My thought for using lime instead of oyster was just the price point really, with the added bonus of getting the PH closer to neutral and some Mg to boot. Planning on re mixing my old soil with more peat and manure so i am assuming the PH will drop pretty good with that addition.
 

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