Soil Testing

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)
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 Retention Index

Soil Sampling Vineyards

Sub Soil Sampling