Why add calcium and magnesium?

Corrects soil deficiencies, prevents blossom end rot in tomatoes, improves soil structure and nutrient uptake.

Dolomitic lime for both Ca+Mg, gypsum for Ca only, Epsom salt for Mg. Test soil first.

Calcium/Magnesium Amendment Calculator

Determine the amount of dolomitic lime or gypsum needed to balance calcium and magnesium levels in your soil.

Determine the amount of dolomitic lime or gypsum needed to balance your soil.

Garden Area (sq ft)

Amendment Type

Current Soil pH

Target Soil pH

The full supporting guide for this calculator is still being expanded. The tool remains accessible while we improve the educational content.

Continue with calculators that answer nearby questions and help compare the next step.

Estimate the amount of lime or sulfur needed to adjust your soil pH to the optimal range for your plants.

Calculate the volume of soil amendment (e.g., compost, sand) needed to achieve a desired percentage mix in your garden beds.