Soil Analysis provides an objective measurement of available nutrients in the soil as well as pH, Electrical Conductivity, Phosphorus Buffering Index (PBI)

Key Benefits

  • Independent Laboratory
  • Rapid Turnaround
  • Uses PBI - the new national P sorption standard.
  • Indication of some Trace Elements
  • Practical recommendations by Area Managers

Nutrients Analysed

Nutrient Symbol Units Used Adequate Range Expected Comments
Phosphorus P ppm (mg/kg) 15 - 45 Dependent on crop/pasture type and soil type.
Potassium K ppm (mg/kg) 40-120 Lupins and Canola are less sensitive to K deficiency. Clover and Medic require higher soil levels
Sulphur S ppm (mg/kg) 5 - 15 Dependent on soil type
Nitrate NO3 ppm (mg/kg) up to 30 Very mobile in the soil. May be lost to leaching.
Ammonium NH4 ppm (mg/kg) up to 20 Stable in the soil as it is a cation, but converts to Nitrate readily.
Copper Cu ppm (mg/kg) >0.3 Soil tests for Copper are a guide only.
Zinc Zn ppm (mg/kg) 0.12-0.5 Dependent on soil pH. The more alkaline the soil (higher pH) the higher the soil Zinc level needs to be.
Organic Carbon O.C. % 1.0 - 3.0 Dependent on soil type and rainfall.
Electrical Conductivity EC(salt) dS/m <0.02 Levels <0.2 are generally considered negligible. Levels >0.8 can be said to be accumulating salt, and should be investigated further.
pH (CaCl2)   >5.0 Economic responses to applying lime to increase pH above 5.0 are doubtful. If subsoil pH is low, it may be necessary to increase topsoil pH >5.5 (CaCl2)
Aluminium (CaCl2)   5.0 As pH declines (becomes more acidic) Aluminium levels can increase in some soil types. High Aluminium levels will affect root growth reducing their ability to explore large volumes of soil and therefore their access to nutrients and soil moisture. (Read the article on soil pH here)
PBI       PBI is a function of soil type. Generally as a soil contains more iron, clay and organic matter, the higher the PBI.
(See article)

Other nutrients can be analyzed on request. Most commonly now farmers are asking for Cation Exchange Capacity (CEC) which involves analyzing for calcium, magnesium and sodium in conjunction with the potassium test to calculate CEC.

Soil Sampling Instructions

Phosphorus Buffering Index

Soil Sampling Vineyards

Sub Soil Sampling