Potassium (K) is being gradually removed from Australia’s cropping soils. Since 2002, average crop yields have increased but K fertiliser use has remained static at around 180 kt K/yr. Soil K reserves declined an average of 4 kg K/ha/yr over the last 20 years. Most cropping paddocks have received no […]
Large areas of West Australian cropping soils have low potassium (K) reserves. Acidity also constrains most of these soils. Potassium deficiencies have become more widespread with intensive cropping, removal of hay or stubbles, and K fertiliser inputs lower than removal rates.
James Easton is the Field Research Manager with CSBP […]
Having sufficient potassium reduces crop damage in frost events. Field trials in Western Australia showed benefits from potassium in wheat and canola. Richard Bell is a researcher at Murdoch University. In this video he explains:
Crops respond more to potassium fertiliser in seasons that stress the plants with drought or frost […]
When both phosphorus (P) and potassium (K) are both low in the subsoil there’s a strategic advantage to managing these two nutrients together. Deep phosphorus (P) deficiency is more common than deep potassium (K) deficiency. It’s unusual to see low subsoil K not accompanied by low subsoil P.
Without adequate […]
Deep banding of phosphorus (P) and potassium (K) fertilisers has shown promising yield responses in some settings, but not in others. Deep-banding trials across Queensland and New South Wales have shown that banding rarely reduces crop yield, but it doesn’t always lead to profitable yield increases.
Some of the variability in […]
Crops may need extra Potassium when they under stress from drought or frost. There is a theoretical basis, and now GRDC funded research is looking into whether applying additional potassium is worthwhile when plants are under stress.
Getting the right combination of drought and frost conditions to get meaningful results from […]
Soil testing is a valuable tool for crop nutrition decision making. The standard 0 – 10cm soil test doesn’t always tell us enough about the crop availability of more mobile nutrients. Nitrogen and Sulphur, as anions (negatively charged), tend to move deeper into the profile with rainfall. On sandy acid […]
Claying by delving brings subsoil clays up to the surface. It’s a proven treatment for water repellency. Integrating clays into sandy topsoils also changes their nutrient status. What happens depends on the specific clay material involved.
Testing of clay material prior to spreading or delving is very important to ensure a […]
Cutting for hay is an option to get some economic value from a failed crop. Growers with an eye to the long term productivity of their paddocks weigh the value of the hay against the value of leaving the crop material in the paddock. Nutrients that would otherwise be recycled […]
David Hall from DAFWA says adding clays to sandy soils can add significant Potassium and Phosphorous, as well as improve the nutrient holding capacity of the soil. Recorded at the National Soil Science conference at the Melbourne Cricket Ground, November 2014.
Proceedings of the Soil Science Australia National Soil Science Conference: