Constraint – Boron

Plant use

  • Boron is a micronutrient 

  • It is mainly involved in the movement of sugars, but also in the metabolism of nitrogen, carbohydrates, and hormones, and in the uptake and efficient use of calcium 

  • Boron may induce both toxicities and deficiencies in Australia


  • Distorted and chlorotic leaves with darker pigmentation along the leaf margins

  • Red and yellow discolouration

  • Poor growth and low seedset


  • Deficiencies often tend to disappear after rainfall since plant roots may be unable to access soil boron in dry soils

  • Yield penalty is very rare


A plant tissue test should be used to confirm boron deficiency. Seek expert advice to determine the appropriate boron types and application rates, and apply a boron fertiliser. Retest in 2-3 years.

Links and Resources

DEPI VIC - What nutrients do plants require? Boron

6.4.6. Plant uses, deficiency and toxicity symptoms, soil and management practices that create risk, and management strategies. Page last updated 2013.

DPI NSW - Boron deficiency in pastures and field crops

Introduction, soils and seasonal conditions likely to increase deficiency, symptoms, crop susceptibility, and control. Published 2004.