Soil Potassium

AUS-AMR-AGR-SOK General Moderate confidence

Benchmark Value

No specific value — see range
Range: 101 to 300 mg/kg
Optimal Range: 101 to 300
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.

Contributing Benchmarks

OptimalRange Primary Point Guard MinimumOnly Guard

Evidence & Context

For Sands, the ideal range is 101 to 150 mg/kg. For Sandy Loams, the ideal range is 121 to 200 mg/kg. For Clay Loams, the ideal range is 161 to 250 mg/kg. For Clays, the ideal range is 181 to 300 mg/kg.

Metric Definition:

Ideal range of available potassium (Colwell K or equivalent) in productive agricultural soils stratified by soil texture

Benchmark Definition:

This benchmark represents the optimal range of soil potassium for agricultural crop production in the Arid Mountain Ranges & Uplands biome, reflecting high nutrient availability and resilience across different soil textures.

Justification:

Based on state-level agricultural extension materials synthesizing decades of field research into practical guidelines for farmers.

Sources (1)

Preview of (PDF) Soil potassium—crop response calibration relationships and criteria for field crops grown in Australia - ResearchGate, accessed July 18, 2025,
(PDF) Soil potassium—crop response calibration relationships and criteria for field crops grown in Australia - ResearchGate, accessed July 18, 2025, Journal

Nutrient Cycling in Australian Savannas on JSTOR - DOI

View Source

Context

  • Region Australia
  • Biome Arid Mountain Ranges & Uplands
  • Land Use Agricultural Crop Production
  • Assessment Agricultural Biodiversity Target
  • Evidence Type HealthyOperationalRange

Lifecycle

  • Status Active
  • Version 1
  • Effective From 10 Jun 2026

Notes

Ranges are stratified by soil texture to reflect different potassium holding capacities and avoid cation imbalances or leaching losses.

Related Benchmarks

Other benchmarks in the AUS-AMR-AGR-SOK family.

40 mg/kg Moderate
Agricultural Crop Production · Agricultural Biodiversity Target
MinimumOnly Active v1