Dolomite lime Fertilizer

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DrFever

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Dolomitic limestone is a type of limestone that includes up to 50 percent dolomite. Normal limestone is primarily made up of calcite and aragonite, but dolomite forms in limestone when the calcium ions in the calcite part of the limestone are replaced by magnesium ions — this process is called dolomitization. Dolomitic limestone was once referred to as magnesian limestone in the United States Geological Survey publications, but is now known as dolostone, dolomite rock, dolomite limestone, or dolomitic limestone. Dolomite is a mineral which contains large amounts of calcium and magnesium, which makes it a good fertilizer for nutrient deficient soil.

In addition to working as a fertilizer, dolomitic limestone is also useful for soils that are too acidic, or have an abnormally low pH level. Adding dolostone for the purpose of raising the soil’s pH level is known as liming. Dolomite stone being sold as liming material typically contains a minimum of 30 percent magnesium.


Dolomite lime fertilizer is certainly allowed in organic gardening. It is not inherently bad, but how it is used in the garden is often detrimental.
The belief is that minerals in your soil are continuously being leached by rain and consequently your soil is always moving towards more acidic.

Dolomite limestone is used to counteract this, to “sweeten” the soil. It can do that, but that doesn’t mean it’s good.

Minerals may or may not be leaching from your soil. If they are, it could be partially because of rain, but there are other reasons, too.

If your soil is low in organic matter, which is often the case, it probably can’t hold onto minerals very well, especially if it is low in clay and high in sand and silt. If you have lots of clay, you probably don’t have much to worry about.

Chemical fertilizers cause acidity, so if you use them, that is part of the problem, too.

Whatever the cause, dolomite lime fertilizer is not the answer. Let’s look at why garden lime is probably not what you want.
The main point I want to make is that even if minerals are leaching from your soil, it doesn’t make sense to blindly go back adding just two of them (the calcium and magnesium in dolomitic lime) without knowing you need them. You might already have too much of one of them. We need to think a little more than that when organic gardening.

Your soil needs a calcium to magnesium ratio of somewhere between 7:1 (sandier soils) and 10:1 (clayier soils). Outside of this range, your soil will often have drainage problems, your plants will often have health problems and insect and disease problems, and you will have weed problems.

One of your most important goals in the garden is to add specific mineral fertilizers to move the calcium to magnesium ratio towards this range.

The problem with dolomite lime? It has a calcium to magnesium ratio of 2:1. That’s way too much magnesium for most soils. Magnesium is certainly an essential mineral. Too much of it, however, causes many problems, compaction being one of the most common, but also pest and weed problems.
You should only use garden lime when you have a soil test showing a huge deficiency of magnesium in your soil.

Even then, calcitic lime (calcium carbonate) is generally the way to go because it has a small amount of magnesium and often a calcium to magnesium ratio of about 6:1, with a calcium content of 30% to 40% or more.
 
your Very welcome lots of people probably didn't know Dolomite lime is actually a fertilizer
 
DrFever said:
your Very welcome lots of people probably didn't know Dolomite lime is actually a fertilizer

Really!? What is the N-P-K?

I use and advocate dolomite, calcitic and other forms of lime, like oyster shell flour, etc, but have never heard of it termed as a fertilizer or applied as such.

I use dolomite in my container mixes and calcitic in my 'soil' garden (lots of clay) after an initial treatment of dolomite (2nd year on). The containers leach, the soil doesn't.

I also use granite dust and other rock dust's but don't count minerals as fertilizer, not per se, as important as they are. I just don't count them with the N-P-K of the other amendments.

I'm probably just getting excited over your use of the term fertilizer even though I agree with you 100% on its use, dolomitic or calcitic.:icon_smile:

Wet
 
Totally agree with you guys these are 100% right when we implement these points in practical life and had a lot of other benefits also....
 
The effects of agricultural lime on soil are:
it increases the pH of acidic soil (the higher the pH the less acidic the soil); in other words, soil acidity is reduced and alkalinity increased
it provides a source of calcium and magnesium for plants <--- is this not a mineral that plants need ??? so it does fall into a fertilizer catagory like zinc iron, mangonese sulphate boron etc
it permits improved water penetration for acidic soils

You ask me what is NPK
Chemical fertilizers and organic fertilizers show their nutrient content with three bold numbers on the package. These numbers represent three different compounds: Nitrogen, Phosphorous, and Potash (Potassium), which we can also describe with the letters N-P-K. The three numbers listed on fertilizer labels correspond to the percentage of these materials found in the fertilizer.However, this theory, which dates to the 1800s, doesn't take into account the dozens of other nutrients and elements that are essential to plant growth such as sulfur, hydrogen, oxygen, carbon, magnesium, etc
It is clear that Nitrogen, Phosphorous, and Potassium are not necessarily the most important elements you need for your plants to grow well. In fact, elements such as carbon, hydrogen, oxygen, sulfur, magnesium, copper, cobalt, sodium, boron, molybdenum, and zinc are just as important to plant development as N-P-K.
 
DrFever said:
The effects of agricultural lime on soil are:
it increases the pH of acidic soil (the higher the pH the less acidic the soil); in other words, soil acidity is reduced and alkalinity increased
it provides a source of calcium and magnesium for plants <--- is this not a mineral that plants need ??? so it does fall into a fertilizer catagory like zinc iron, mangonese sulphate boron etc
it permits improved water penetration for acidic soils
:yeahthat:

Basically, we are in 420% agreement and I'm hung up on semantics. :bolt:

IDK, I just sort of figure lime as by itself, not really a rock dust with lots of trace, nor a blood/bone/kelp sort of thing either.

It is what it is and essential in my scheme of growing.:icon_smile:

Wet
 

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