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. The scoring engine uses 6 benchmarks together — the OptimalRange form drives the primary score, while 5 guard(s) constrain the result.
Contributing Benchmarks
Evidence & Context
Synthesizing data from studies on wheat, pasture, and forestry, a soil level of < 50 mg/kg (Colwell K) represents a clear point of deficiency.
Available soil potassium (Colwell K) concentration in topsoil
A soil potassium level below 50 mg/kg is critically deficient, compromising forest health, productivity, and drought resilience in arid mountain production forestry.
Multiple agricultural and ecological studies in Australia agree on this threshold as a critical deficiency point.
Sources (1)
Long-term rundown of plant-available potassium in Western Australia requires a re-evaluation of potassium management for grain production: a review - BioOne Complete
View SourceSupporting Sources (3)
Additional references from the underlying research that informed this benchmark.
Soil Inorganic Carbon, the Other and Equally Important Soil Carbon Pool: Distribution, Controlling Factors, and the Impact of C
View SourceLittle left to lose: deforestation and forest degradation in Australia since European colonization | Journal of Plant Ecology | Oxford Academic
View SourceAgriculture Victoria. (2025). Understanding soil tests for pastures. Farm Management.
View Source