Development and application of a model for calculating the risk of stem and root lodging in maize

•A model of anchorage strength with spread of the root plate as its main input was shown to be applicable for maize.•Increasing plant population reduced the anchorage and stem failure wind speeds, thus increasing lodging risk.•Changes in N fertiliser had a small effect on the lodging associated plant characters.•Stem and root failure wind speed were influenced most by variation in stem strength and root plate spread respectively.•Leaf area index measured at leaf 4, 6 or 8 stages was a good indicator of a crop’s future risk of lodging.