Soil Potassium
Benchmark Value
Scoring Curve
This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context.
Evidence & Context
Indicator Name: Soil Potassium Reference Value: 160 - 300 mg/kg (for Loamy and Clayey soils); 100 - 200 mg/kg (for Sandy and Sandy Loam soils) Unit: mg/kg
Available soil potassium measured as Colwell K, representing plant-available potassium in soil.
Optimal range for available potassium in loam, clay loam, and clay soils for conservation landscapes.
This range is based on Victorian agricultural guides and supported by evidence showing significant K depletion when native vegetation is converted to agriculture.
Sources (1)
Agriculture Victoria. (2025). Understanding soil tests for pastures. Farm Management.
View SourceSupporting Sources (38)
Additional references from the underlying research that informed this benchmark.
Putting the P in Ptilotus: a phosphorus-accumulating herb native to Australia - PMC
View SourceNutrient Cycling in Australian Savannas on JSTOR - DOI
View SourceFLC Flinders Chase Land System
View Source(PDF) Final report Scoping Study of Soil Management in Livestock Grazing Systems
View SourceGreat Western Woodlands, Ground Water Data, 2014 - TERN Data Discovery Portal, accessed July 10, 2025,
View SourceSOIL TESTING
View SourceComment: Potassium in soil is running low, threatening global food security - study proposes way out | UCL News - UCL – University College London
View SourceLiving with high potassium: Balance between nutrient acquisition and K-induced salt stress signaling
View SourceEFFECTS OF AGRICULTURAL MANAGEMENT ON SOIL CARBON AND pH IN THE DOUGLAS DALY REGION OF THE NORTHERN TERRITORY, accessed July 16, 2025,
View SourceLong-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - CSIRO Publishing, accessed July 17, 2025
View SourceDigital soil mapping of key soil properties over New South Wales - NSW Government
View SourceFlinders Ranges - UNESCO World Heritage Centre, accessed July 29, 2025
View SourceGeol ogy ofth e Flin ders Rang es Nati onal Park
View SourceWhat are the optimum nutrient targets for pastures? - Soil Health Knowledgebase
View SourceLong-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - BioOne Complete
View SourceMacDonnell Ranges - Wikipedia, accessed July 31, 2025
View SourceA Dive into the Geological History of the Red Centre - Tourism Central Australia
View SourceSoil potassium relationships, uptake efficiency and availability for six distinctive soils in central and southern New South Wales, Australia - CSIRO PUBLISHING | Soil Research
View SourceMonitoring and forecasting drought through the assimilation of satellite water observations Siyuan Tian - ANU Open Research, accessed May 27, 2025
View SourcePotassium In Soil Explained - Soil Quality Knowledge Base
View SourcePlantation tree growth responses to P, N, K and minor and trace elements on low fertility savanna soils - CSIRO Publishing, accessed July 20, 2025,
View SourcePotassium | Fact Sheets | soilquality.org.au
View SourcePotassium and sulphur - emerging deficiencies in the southern region - GRDC
View SourceOptimal potassium to magnesium ratio in soils ? | ResearchGate
View SourcePotassium Control of Plant Functions: Ecological and Agricultural Implications - MDPI
View SourcePotassium: A Vital Regulator of Plant Responses and Tolerance to Abiotic Stresses - MDPI, accessed July 28, 2025,
View SourceSoil and Landscape Grid National Soil Attribute Maps - Total Nitrogen (3" resolution) - Release 2 - CSIRO Data Access Portal, accessed July 13, 2025,
View SourceSoil and Landscape Grid National Soil Attribute Maps - Cation Exchange Capacity (3" resolution) - Release 1 - Research Data Australia
View SourceSoil and Landscape Grid of Australia - CSIRO
View SourceSoil Constraints in an Arid Environment—Challenges, Prospects, and Implications - MDPI
View SourceSoil health stocktake Queensland - GRDC, accessed May 11, 2025
View SourceUnderstanding soil tests for pastures | Soil | Farm management ..., accessed July 17, 2025
View SourceReview and Synthesis of Potassium Dynamics and Crop Response in Australian Agriculture
View SourceSubsoil testing required to detect the rundown of soil potassium to deficient levels for wheat production on loam-textured soils - ResearchGate
View SourceAustralian National Soil Information System
View SourceThe Dynamics of Potassium in some Australian soils - ResearchGate, accessed July 24, 2025
View SourceUnder the radar: Potassium on loamy soil - SoilsWest
View SourceV*. Clearing and burning brigalow (Acacia harpophylla) in Queensland, Australia, temporarily increases surface soil fertility prior to nutrient decline under cropping or grazing - CSIRO Publishing, accessed July 18, 2025,
View Source