Calcium (Ca)
A secondary macronutrient that strengthens cell walls and supports root development. Calcium is rarely deficient in established lawns but plays an important role in soil pH management. Lime (calcium carbonate) is often applied to raise soil pH and as a calcium source simultaneously.
Calcium is essential for cell wall formation and root tip development in grass. Deficiency is uncommon in most regions but can occur in acidic, sandy, or heavily leached soils.
Soil pH connection: Most calcium applications are made indirectly through lime (calcium carbonate or calcium magnesium carbonate/dolomite). When lime is applied to raise pH in acidic soils, it also adds calcium.
Application: Agricultural lime (calcitic lime for calcium-only, dolomitic lime for calcium + magnesium). Gypsum (calcium sulfate) adds calcium without affecting pH — useful in neutral or slightly alkaline soils.
More on Micronutrients
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