Soil Potassium

AUS-TDG-LVG-SOK General Moderate confidence

Benchmark Value

No specific value — see range
Range: 161 to 250 mg/kg
Optimal Range: 161 to 250
Direction: Higher is desirable ↑
Form: OptimalRange

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 3 benchmarks together — the OptimalRange form drives the primary score, while 2 guard(s) constrain the result.

Evidence & Context

Based on this interpretative approach, the following reference ranges for Colwell K are proposed: For Clay Loams: 161-250 mg/kg

Metric Definition:

Colwell K soil potassium concentration in mg/kg

Benchmark Definition:

This benchmark represents the optimal range of soil potassium concentration in clay loam soils under sustainable grazing in temperate dry woodlands and native grasslands in Australia.

Justification:

This range is derived from the "Ideal" category provided by Agriculture Victoria and the "Adequate" range from the Corangamite CMA Soil Health Knowledge Base, interpreted for native ecosystems under sustainable grazing.

Sources (2)

Preview of Lowland Native Grassland Ecosystem Condition Monitoring Plan
Lowland Native Grassland Ecosystem Condition Monitoring Plan

Understanding soil tests for pastures | Soil | Farm management ...

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Preview of Understanding soil tests for pastures | Soil | Farm management ..., accessed May 12, 2025
Understanding soil tests for pastures | Soil | Farm management ..., accessed May 12, 2025 Government

Understanding soil tests for pastures

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Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

Preview of Potassium | Fact Sheets | soilquality.org.au, accessed July 10, 2025
Potassium | Fact Sheets | soilquality.org.au, accessed July 10, 2025
Contextual Support Government

Potassium - Tas | Fact Sheets | soilquality.org.au, accessed May 11, 2025,

View Source
Preview of www.act.gov.au, accessed May 11, 2025,
www.act.gov.au, accessed May 11, 2025,
Contextual Support Journal

www.act.gov.au, accessed May 11, 2025,

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