What is dolomite?
What is dolomite? If you’ve ever wondered what is dolomite, it is a naturally occurring rock commonly sold as dolomite lime that raises soil pH while adding calcium and magnesium. Understanding how to work with your soil profile will empower you to garden with more confidence and support stronger, healthier plant growth. Dolomite contains the essential minerals calcium carbonate (CaCO₃) and magnesium carbonate (MgCO₃). Garden lime, a similar product, also raises pH but works more quickly and only supplies calcium. As a result, dolomite is a gentler option and better suited where magnesium is also needed.
Why gardeners use dolomite
1. To reduce soil acidity (raise pH)
This is especially useful in
- Heavy rainfall areas
- Gardens where fertilisers have acidified the soil.
- Veggie beds needing a more neutral or alkaline pH.
2. To add magnesium
Magnesium is vital for chlorophyll production, so plants need it for strong green growth.
Dolomite is ideal when
- Leaves are yellowing between the veins (magnesium deficiency due to a very low pH).
- You grow magnesium-hungry plants like citrus.
3. To add calcium
Calcium strengthens cell walls and helps prevent issues like
- Blossom end rot in tomatoes and capsicums
- Poor root development
- Weak stems
How to use dolomite in the garden
- Sprinkle evenly over the soil surface
- Lightly rake in and then water
- Always check the packaging for application rates.
