New Zealand 2025: yield up in 75% of trials through a brutal season
2025 was New Zealand's fourth-hottest year on record. In a season disrupted by extreme weather, Messium still improved yield in three out of four trials - a median benefit of +0.17 t/ha and +NZD$115/ha, with yields independently validated by ADAS.
A season that tested everyone
By ADAS's own account, 2025 was New Zealand's fourth-hottest year on record, with widespread above-average temperatures and a developing La Niña. On the Canterbury plains, rainfall was high in April and June but below average from July to November. Wheat yields were lower and more variable than usual, storms in late October pushed some applications past their optimal window, and hail flattened crops in isolated areas.
It was, in short, the kind of year that makes nitrogen decisions harder, not easier. That context matters for reading the results.
The headline result
Using weighbridge-based yield analysis, Messium improved yield in 75% of trials. The median modelled yield benefit was +0.17 t/ha, and the median gross margin benefit was +NZD$115/ha - around £51/ha - against each farm's own standard practice.
We are equally clear about the two that did not work: in one trial the same total nitrogen was applied, and in another the farm standard out-performed Messium while using less. Reporting the misses is the point - it is how a validation programme stays honest.
Independently validated by ADAS
As in the UK, ADAS independently validated the yield results using their Agronomics methodology. Messium funded this analysis at every site - NZD$1,900 per site - with an individual report for each farm.
Coverage and scale
Better models, year on year
The 2024 New Zealand trials showed strong nitrogen savings in a more normal season. 2025 stress-tested the models against extreme conditions - exactly the data needed to make the system more robust. Holding a positive result in three of four trials through a year this difficult is, if anything, the more meaningful proof.
The bottom line
In one of New Zealand's hardest growing years, Messium improved yield in three out of four trials for a median +NZD$115/ha - independently validated, openly reported, and built on a season's worth of new data that makes 2026 stronger still.