Dolomite vs Agricultural Lime (Limestone) — Which Should You Use to Correct Soil pH?

Introduction

When a soil test comes back acidic, the standard advice is "add lime" — but there are two common liming materials, and choosing between them matters. Agricultural lime (calcitic limestone) and dolomite both raise soil pH, but only one also supplies magnesium. This guide compares dolomite and limestone so you pick the right liming material for your soil and crop.

The Core Difference: Magnesium

Both materials are carbonates that neutralise soil acidity, but their nutrient content differs:

• Agricultural lime (calcitic limestone): calcium carbonate (CaCO₃) — supplies calcium and raises pH.
• Dolomite: calcium-magnesium carbonate (CaMg(CO₃)₂) — supplies calcium and magnesium and raises pH.

Radhe Enterprise dolomite ball granules run 28–32% CaO and 18–22% MgO — that magnesium content is the whole reason to choose dolomite over plain lime.

Comparison Table

| Factor | Agricultural Lime (Calcitic) | Dolomite | |--------|------------------------------|----------| | Chemistry | CaCO₃ | CaMg(CO₃)₂ | | Raises soil pH? | Yes | Yes | | Supplies calcium? | Yes | Yes | | Supplies magnesium? | No | Yes (18–22% MgO) | | Best when soil is… | Acidic but Mg-sufficient | Acidic AND Mg-deficient | | Risk if misused | Can worsen Ca:Mg imbalance | Over-application on Mg-rich soil |

When to Choose Dolomite

Choose dolomite when your soil is acidic and low in magnesium — a very common combination, especially on:

• Sandy soils, which leach magnesium readily.
• High-rainfall regions, where magnesium washes out of the profile.
• Intensively cropped fields where magnesium has been mined out by successive harvests.
• Crops with high magnesium demand (see ).