Broad nutrition resources are outlined in the Agronomists Toolkit. Specific nutrient categories are listed below:



Constraint – Magnesium 

Plant use

  • Magnesium is a macronutrient

  • Magnesium is an essential component of chlorophyll and is required for the transport of phosphorus

  •  Magnesium deficiencies are rare and normally transient


No yield penalties have yet been recorded


soil test or a plant tissue test should be used to confirm magnesium deficiency. A dolomite fertiliser can then be applied in appropriate quantities. Limiting the application of nitrogenous or potassium fertilisers to required amounts, rather than over supplying, may also increase the availability of magnesium. 

Links and Resources

AOF - Canola nutrition. Magnesium

Page 6 of 8. Information on magnesium deficiency.

DEPI VIC - What nutrients do plants require? Magnesium

Section 6.3.6.  Symptoms of deficiency, fertiliser supplements, animal health implications and preventative measures. Page last updated 2013.

DPI NSW - Soil acidity and liming. Magnesium

Impacts of soil acidity, recognising soil acidity, causes, reduction in production, reducing the impact, management, estimating rates of soil acidification, and further information. Specific information on magnesium on pages 15 and 16 of 24. Published 2005.

GRDC - Best Practice Management Guide. Magnesium

Page 37 of 92. Information on magnesium deficiency. Published 2009.

IPNI - Canola 4R Guide. Magnesium

Page 16 of 21. Very brief information on magnesium deficiency. Published 2013.