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Possible to add too much Calcium & Magnesium to soil?

i have added some calcium nitrate to all my beds and some epsom salt....not too much, but enough, i hope

just a quick question....i have read that you can safely add both of these things to your garden and not be too picky about overdosing

just out of curiosity, is that true? adding too much of either something the average gardener needs to worry about?

Fertilizer...Kelp Extract...Compost Tea...Fish Emulsion....Manure (tea)...etc....A little all the time is better than a lot at once... thus endeth the lesson....

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Location: hawaii, zone 12a 587 ft elev.

Re: Possible to add too much Calcium & Magnesium to soil?

I have not used calcium nitrate, it is used in hydroponics and the farm does do hydroponics but the controller tests and meters the different components to the system from the tanks. It contains nitrogen as well as calcium salts. Too much of any salt, I would think would not be a good idea. Epsom salt contains magnesium. You will need to watch the ratio of Ca:Mg or magnesium uptake will be affected.


The magnesium cycle is very similar to the calcium cycle. Like calcium, magnesium can be contained by:

Magnesium bearing minerals
The cation exchange capacity
Soil solution
There are a variety of primary and secondary minerals that contain magnesium. Magnesium becomes available when these minerals dissolve, or weather. After release, magnesium is held by the cation exchange capacity of the soil particles or resides in the soil solution. Magnesium in the soil solution may precipitate into secondary minerals, be taken up by plants, or leached from the soil.

Factors determining availability
Similarly to calcium, magnesium is limited in soils that are:

Inherently low in magnesium-containing minerals
Highly leached
Limed with non-magnesium-containing material
Contain excessive amounts of other cations, such as potassium, calcium and ammonium, which compete with magnesium and reduces its presence on the cation exchange capacity
With a Ca: Mg ratio greater than 10:1 to 15:1, magnesium will likely be deficient.
Happy gardening in Hawaii. Gardens are where people grow.

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Re: Possible to add too much Calcium & Magnesium to soil?

A $10 soil test by a professional soil testing lab will take all the guesswork out of the equation. Soil needs to be at a balance to do its best job of growing. Too much of one or more minerals in the soil could greatly affect conditions.

Since my particular soil is high in calcium and magnesium adding any more would be a disaster. That is why I take the advise of the pros. They know my area and soil and their thousands of dollars worth of equipment and years of experience is important.
Paul F

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