With a wide rage of soil colours found in Australian soil, determined by the amount and type of organic matter and iron oxides, the type of parent material/rock the soil is formed from, and the water content — what is your soil telling you?
Red colours in soil are usually due to iron oxides. Poorly drained soils may contain blue, grey and green colours. Some soils are the same colour from the top to the bottom. Other soils vary in colour as you dig deeper.
Know your soil!Soil pH determines the availability of different nutrients to plants, making it very important for plant growth — how can you use soil pH to your advantage? Under acid conditions, calcium, magnesium and phosphorus become deficient, while aluminium and manganese become too available, causing toxicity. Under alkaline conditions, zinc, copper, boron and manganese become deficient. However, most nutrients are readily available to plants when soil pH is near neutral.
Fertilisers such as crushed sulfur and some ammoniumbased nitrogen fertilisers lower pH and make soil more acid. They are useful for soils with problems caused by high pH. When soils are too acidic for a particular crop, lime (calcium carbonate) or dolomite (calcium and magnesium carbonate) can be used to increase the pH to the desired level.
Changing soil pH won’t work immediately—allow a couple of months for changes to occur. Measure pH regularly to check your soil’s progress and refer back to these spreadsheets to ensure your soil is working for you.
You can diagnose your soil. Learn how with the Southern Queensland Landscapes fact sheet.
Southern Queensland Landscapes fact sheet