Why You Should Not Mix Calcium Nitrate and Magnesium Sulphate
In modern agriculture, water-soluble fertilizers like Calcium Nitrate and Magnesium Sulphate are commonly used for efficient nutrient delivery through fertigation or foliar spray. However, mixing these two fertilizers in the same tank can lead to unexpected problems.
The Science Behind the Issue :
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Calcium Nitrate supplies crops with Calcium (Ca) and fast-acting Nitrate Nitrogen (NO₃⁻).
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Magnesium Sulphate provides Magnesium (Mg) and Sulphur (S), which are essential for photosynthesis and protein formation.
When these two fertilizers are mixed in concentrated form, the Calcium ions from Calcium Nitrate react with the Sulphate ions from Magnesium Sulphate. This reaction forms Calcium Sulphate, a compound that is only slightly soluble in water.
As a result:
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A white precipitate forms (commonly known as gypsum)
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Drip lines, filters, and spray nozzles can become clogged
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Nutrient availability to the plant decreases
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Fertilizer efficiency drops
Best Practices for Application
If your crop requires both calcium and magnesium:
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Use separate tanks for fertigation:
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One for Calcium Nitrate
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Another for Magnesium Sulphate
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Or apply them at different times if you're using only one tank or doing manual application
