Reduced nitrogen and seeding rates in frost prone landscapes does not reduce frost damage

Document Type

Conference Proceeding

Publication Date


Conference Title

System Solutions for Complex Problems: Proceedings of the 20th Australian Agronomy Conference - 18-22 September 2022

Place of Publication



Frost, wheat, nitrogen, seeding rate, canopy management, plant density


Agronomy and Crop Sciences


Reducing nitrogen and seeding rate to half of farmer practice can reduce frost severity and duration but not frost damage. In areas of low frost-risk or in non-frosted crops there is, as expected, a clear financial response to nitrogen. In moderately frosted crops with significant frost damage at stem elongation or pre heading/booting, there is likely to be either no response or a small, positive response in yield and gross margin to nitrogen application. In crops severely frost damaged at flowering and those frosted later during grain-fill there is not likely to be any loss in gross margin with nitrogen application in line with local agronomic practice and long term yield potential. In frost-prone landscapes, maintaining normal grower practice for seeding rate and nitrogen for local yield potential is likely to give the greatest financial return in years without frost, some financial advantage in years with moderate frost and, importantly, no negative consequences in years with severe frost.